mirror of
https://github.com/cc65/cc65.git
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Merge pull request #131 from greg-king5/refine-crt
Made the crt0.s source files comments be consistent with each other.
This commit is contained in:
Oliver Schmidt
commit
76283e1b45
@ -24,76 +24,76 @@
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ldx #$FF
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txs ; Init stack pointer
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; Switch in LC bank 2 for W/O
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; Switch in LC bank 2 for W/O.
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bit $C081
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bit $C081
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; Set source start address
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; Set the source start address.
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lda #<(__ZPSAVE_RUN__ + __INIT_SIZE__)
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ldy #>(__ZPSAVE_RUN__ + __INIT_SIZE__)
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sta $9B
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sty $9C
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; Set source last address
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; Set the source last address.
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lda #<(__ZPSAVE_RUN__ + __INIT_SIZE__ + __LC_LAST__ - __LC_START__)
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ldy #>(__ZPSAVE_RUN__ + __INIT_SIZE__ + __LC_LAST__ - __LC_START__)
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sta $96
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sty $97
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; Set destination last address
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; Set the destination last address.
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lda #<__LC_LAST__
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ldy #>__LC_LAST__
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sta $94
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sty $95
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; Call into Applesoft Block Transfer Utility - which handles zero
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; sized blocks well - to move content of the LC memory area
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; Call into the Applesoft Block Transfer Utility -- which handles zero-
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; sized blocks well -- to move the content of the LC memory area.
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jsr $D396 ; BLTU + 3
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; Set source start address
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; Set the source start address.
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lda #<__ZPSAVE_RUN__
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ldy #>__ZPSAVE_RUN__
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sta $9B
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sty $9C
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; Set source last address
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; Set the source last address.
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lda #<(__ZPSAVE_RUN__ + __INIT_SIZE__)
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ldy #>(__ZPSAVE_RUN__ + __INIT_SIZE__)
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sta $96
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sty $97
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; Set destination last address
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; Set the destination last address.
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lda #<(__INIT_RUN__ + __INIT_SIZE__)
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ldy #>(__INIT_RUN__ + __INIT_SIZE__)
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sta $94
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sty $95
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; Call into Applesoft Block Transfer Utility - which handles moving
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; overlapping blocks upwards well - to move the INIT segment
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; Call into the Applesoft Block Transfer Utility -- which handles moving
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; overlapping blocks upwards well -- to move the INIT segment.
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jsr $D396 ; BLTU + 3
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; Delegate all further processing to keep the STARTUP segment small
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; Delegate all further processing, to keep the STARTUP segment small.
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jsr init
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; Avoid re-entrance of donelib. This is also the _exit entry
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; Avoid a re-entrance of donelib. This is also the exit() entry.
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_exit: ldx #<exit
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lda #>exit
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jsr reset ; Setup RESET vector
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; Switch in ROM in case it wasn't already switched in by a RESET
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; Switch in ROM, in case it wasn't already switched in by a RESET.
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bit $C082
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; Call module destructors
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; Call the module destructors.
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jsr donelib
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; Restore the original RESET vector
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; Restore the original RESET vector.
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exit: ldx #$02
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: lda rvsave,x
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sta SOFTEV,x
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dex
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bpl :-
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; Copy back the zero page stuff
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; Copy back the zero-page stuff.
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ldx #zpspace-1
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: lda zpsave,x
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sta sp,x
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@ -111,17 +111,17 @@ exit: ldx #$02
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.segment "INIT"
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; Save the zero page locations we need
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; Save the zero-page locations that we need.
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init: ldx #zpspace-1
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: lda sp,x
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sta zpsave,x
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dex
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bpl :-
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; Clear the BSS data
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; Clear the BSS data.
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jsr zerobss
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; Save the original RESET vector
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; Save the original RESET vector.
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ldx #$02
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: lda SOFTEV,x
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sta rvsave,x
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@ -135,58 +135,58 @@ init: ldx #zpspace-1
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lda #>_exit
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jsr reset ; Setup RESET vector
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; Check for ProDOS
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; Check for ProDOS.
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ldy $BF00 ; MLI call entry point
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cpy #$4C ; Is MLI present? (JMP opcode)
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bne basic
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; Check ProDOS system bit map
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; Check the ProDOS system bit map.
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lda $BF6F ; Protection for pages $B8 - $BF
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cmp #%00000001 ; Exactly system global page is protected
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bne basic
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; No BASIC.SYSTEM so quit to ProDOS dispatcher instead
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; No BASIC.SYSTEM; so, quit to the ProDOS dispatcher instead.
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lda #<quit
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ldx #>quit
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sta done+1
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stx done+2
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; No BASIC.SYSTEM so use addr of ProDOS system global page
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; No BASIC.SYSTEM; so, use the addr of the ProDOS system global page.
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lda #<$BF00
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ldx #>$BF00
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bne :+ ; Branch always
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; Get highest available mem addr from BASIC interpreter
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; Get the highest available mem addr from the BASIC interpreter.
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basic: lda HIMEM
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ldx HIMEM+1
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; Setup the C stack
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; Set up the C stack.
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: sta sp
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stx sp+1
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; Enable interrupts as old ProDOS versions (i.e. 1.1.1)
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; jump to SYS and BIN programs with interrupts disabled
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; Enable interrupts, as old ProDOS versions (i.e. 1.1.1)
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; jump to SYS and BIN programs with interrupts disabled.
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cli
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; Call module constructors
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; Call the module constructors.
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jsr initlib
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; Switch in LC bank 2 for R/O
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; Switch in LC bank 2 for R/O.
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bit $C080
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; Push arguments and call main()
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; Push the command-line arguments; and, call main().
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jmp callmain
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.code
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; Setup RESET vector
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; Set up the RESET vector.
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reset: stx SOFTEV
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sta SOFTEV+1
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eor #$A5
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sta PWREDUP
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return: rts
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; Quit to ProDOS dispatcher
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; Quit to the ProDOS dispatcher.
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quit: jsr $BF00 ; MLI call entry point
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.byte $65 ; Quit
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.word q_param
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@ -32,8 +32,8 @@
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.segment "STARTUP"
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rts ; fix for SpartaDOS / OS/A+
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; they first call the entry point from AUTOSTRT and
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; then the load addess (this rts here).
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; They first call the entry point from AUTOSTRT; and
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; then, the load address (this rts here).
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; We point AUTOSTRT directly after the rts.
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; Real entry point:
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@ -44,11 +44,11 @@ start:
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jsr sram_init
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.endif
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; Clear the BSS data
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; Clear the BSS data.
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jsr zerobss
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; Setup the stack
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; Set up the stack.
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tsx
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stx SP_save
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@ -62,7 +62,7 @@ start:
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.else
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; Report memory usage
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; Report the memory usage.
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lda APPMHI
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sta APPMHI_save ; remember old APPMHI value
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@ -73,60 +73,60 @@ start:
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lda MEMTOP
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sbc #<__RESERVED_MEMORY__
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sta APPMHI ; initialize our APPMHI value
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sta sp ; setup runtime stack part 1
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sta sp ; set up runtime stack part 1
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lda MEMTOP+1
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sbc #>__RESERVED_MEMORY__
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sta APPMHI+1
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sta sp+1 ; setup runtime stack part 2
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sta sp+1 ; set up runtime stack part 2
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.endif
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; Call module constructors
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; Call the module constructors.
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jsr initlib
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; Set left margin to 0
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; Set the left margin to 0.
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lda LMARGN
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sta LMARGN_save
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ldy #0
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sty LMARGN
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; Set keyb to upper/lowercase mode
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; Set the keyboard to upper-/lower-case mode.
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ldx SHFLOK
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stx SHFLOK_save
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sty SHFLOK
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; Initialize conio stuff
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; Initialize the conio stuff.
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dey ; Set Y to $FF
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sty CH ; remove keypress which might be in the input buffer
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; Push arguments and call main
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; Push the command-line arguments; and, call main().
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jsr callmain
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; Call module destructors. This is also the _exit entry.
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; Call the module destructors. This is also the exit() entry.
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_exit: jsr donelib ; Run module destructors
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; Restore system stuff
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; Restore the system stuff.
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ldx SP_save
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txs ; Restore stack pointer
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; Restore left margin
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; Restore the left margin.
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lda LMARGN_save
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sta LMARGN
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; Restore kb mode
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; Restore the kb mode.
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lda SHFLOK_save
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sta SHFLOK
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; Restore APPMHI
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; Restore APPMHI.
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lda APPMHI_save
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sta APPMHI
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@ -147,8 +147,8 @@ _exit: jsr donelib ; Run module destructors
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sta MEMTOP+1
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; Issue a GRAPHICS 0 call (copied'n'pasted from TGI drivers) in
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; order to restore screen memory to its defailt location just
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; Issue a GRAPHICS 0 call (copied'n'pasted from the TGI drivers), in
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; order to restore screen memory to its default location just
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; before the ROM.
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jsr findfreeiocb
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@ -169,7 +169,7 @@ _exit: jsr donelib ; Run module destructors
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lda #0
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sta ICBLH,x
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jsr CIOV_org
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; No error checking here, shouldn't happen(tm), and no way to
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; No error checking here, shouldn't happen(TM); and, no way to
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; recover anyway.
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lda #CLOSE
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@ -178,12 +178,12 @@ _exit: jsr donelib ; Run module destructors
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.endif
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; Turn on cursor
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; Turn on the cursor.
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ldx #0
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stx CRSINH
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; Back to DOS
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; Back to DOS.
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rts
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@ -17,29 +17,29 @@
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start:
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; Clear the BSS data
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; Clear the BSS data.
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jsr zerobss
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; initialize data
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; Initialize the data.
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jsr copydata
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; setup the stack
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; Set up the stack.
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lda #<(__RAM_START__ + __RAM_SIZE__ - __RESERVED_MEMORY__)
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sta sp
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lda #>(__RAM_START__ + __RAM_SIZE__ - __RESERVED_MEMORY__)
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sta sp+1 ; Set argument stack ptr
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; Call module constructors
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; Call the module constructors.
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jsr initlib
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; Push arguments and call main()
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; Push the command-line arguments; and, call main().
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jsr callmain
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; Call module destructors. This is also the _exit entry.
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; Call the module destructors. This is also the exit() entry.
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_exit: jsr donelib ; Run module destructors
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@ -22,21 +22,21 @@
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Start:
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; Switch to the second charset
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; Switch to the second charset.
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lda #14
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jsr BSOUT
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; Before doing anything else, we have to setup our banking configuration.
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; Otherwise just the lowest 16K are actually RAM. Writing through the ROM
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; to the underlying RAM works, but it is bad style.
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; Before doing anything else, we have to set up our banking configuration.
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; Otherwise, just the lowest 16K are actually RAM. Writing through the ROM
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; to the underlying RAM works; but, it is bad style.
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lda MMU_CR ; Get current memory configuration...
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pha ; ...and save it for later
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lda #MMU_CFG_CC65 ; Bank0 with kernal ROM
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lda #MMU_CFG_CC65 ; Bank0 with Kernal ROM
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sta MMU_CR
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; Save the zero page locations we need
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; Save the zero-page locations that we need.
|
||||
|
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ldx #zpspace-1
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L1: lda sp,x
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@ -44,11 +44,11 @@ L1: lda sp,x
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dex
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bpl L1
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; Clear the BSS data
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; Clear the BSS data.
|
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|
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jsr zerobss
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|
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; Save system stuff and setup the stack
|
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; Save some system stuff; and, set up the stack.
|
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|
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pla ; Get MMU setting
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sta mmusave
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@ -61,27 +61,27 @@ L1: lda sp,x
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lda #>(__RAM_START__ + __RAM_SIZE__ + __STACKSIZE__)
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sta sp+1 ; Set argument stack ptr
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|
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; Call module constructors
|
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; Call the module constructors.
|
||||
|
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jsr initlib
|
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|
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; Set the bank for the file name to our execution bank. We must do this,
|
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; *after* calling constructors, because some of them may depend on the
|
||||
; original value of this register.
|
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; Set the bank for the file name to our execution bank. We must do this
|
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; *after* calling the constructors because some of them might depend on
|
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; the original value of this register.
|
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|
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lda #0
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sta FNAM_BANK
|
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|
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; Push arguments and call main()
|
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; Push the command-line arguments; and, call main().
|
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|
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jsr callmain
|
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|
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; Back from main (this is also the _exit entry). Run module destructors
|
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; Back from main() [this is also the exit() entry]. Run the module destructors.
|
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|
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_exit: pha ; Save the return code on stack
|
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jsr donelib
|
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|
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; Copy back the zero page stuff
|
||||
; Copy back the zero-page stuff.
|
||||
|
||||
ldx #zpspace-1
|
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L2: lda zpsave,x
|
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@ -89,19 +89,19 @@ L2: lda zpsave,x
|
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dex
|
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bpl L2
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|
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; Place the program return code into ST
|
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; Place the program return code into BASIC's status variable.
|
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|
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pla
|
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sta ST
|
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|
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; Reset the stack and the memory configuration
|
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; Reset the stack and the memory configuration.
|
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|
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ldx spsave
|
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txs
|
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ldx mmusave
|
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stx MMU_CR
|
||||
|
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; Done, return to BASIC
|
||||
; Done, return to BASIC.
|
||||
|
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rts
|
||||
|
||||
|
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@ -1,8 +1,8 @@
|
||||
;
|
||||
; Startup code for cc65 (C16 version)
|
||||
;
|
||||
; Note: The C16 is actually the Plus/4 with just 16KB of memory. So many
|
||||
; things are similar here, and we even use the plus4.inc include file.
|
||||
; Note: The C16 is actually the Plus/4 with just 16KB of memory. So, many
|
||||
; things are similar here; and, we even use the plus4.inc include file.
|
||||
;
|
||||
|
||||
.export _exit
|
||||
@ -22,7 +22,7 @@
|
||||
|
||||
Start:
|
||||
|
||||
; Save the zero page locations we need
|
||||
; Save the zero-page locations that we need.
|
||||
|
||||
ldx #zpspace-1
|
||||
L1: lda sp,x
|
||||
@ -30,16 +30,16 @@ L1: lda sp,x
|
||||
dex
|
||||
bpl L1
|
||||
|
||||
; Switch to second charset
|
||||
; Switch to the second charset.
|
||||
|
||||
lda #14
|
||||
jsr BSOUT
|
||||
|
||||
; Clear the BSS data
|
||||
; Clear the BSS data.
|
||||
|
||||
jsr zerobss
|
||||
|
||||
; Save system stuff and setup the stack
|
||||
; Save some system stuff; and, set up the stack.
|
||||
|
||||
tsx
|
||||
stx spsave ; save system stk ptr
|
||||
@ -53,20 +53,20 @@ L1: lda sp,x
|
||||
MemOk: stx sp
|
||||
sty sp+1 ; set argument stack ptr
|
||||
|
||||
; Call module constructors
|
||||
; Call the module constructors.
|
||||
|
||||
jsr initlib
|
||||
|
||||
; Push arguments and call main()
|
||||
; Push the command-line arguments; and, call main().
|
||||
|
||||
jsr callmain
|
||||
|
||||
; Call module destructors. This is also the _exit entry.
|
||||
; Call the module destructors. This is also the exit() entry.
|
||||
|
||||
_exit: pha ; Save the return code on stack
|
||||
jsr donelib ; Run module destructors
|
||||
|
||||
; Copy back the zero page stuff
|
||||
; Copy back the zero-page stuff.
|
||||
|
||||
ldx #zpspace-1
|
||||
L2: lda zpsave,x
|
||||
@ -74,17 +74,17 @@ L2: lda zpsave,x
|
||||
dex
|
||||
bpl L2
|
||||
|
||||
; Store the return code into ST
|
||||
; Store the return code into BASIC's status variable.
|
||||
|
||||
pla
|
||||
sta ST
|
||||
|
||||
; Restore the stack pointer
|
||||
; Restore the stack pointer.
|
||||
|
||||
ldx spsave
|
||||
txs
|
||||
|
||||
; Back to BASIC
|
||||
; Back to BASIC.
|
||||
|
||||
rts
|
||||
|
||||
|
||||
@ -23,7 +23,7 @@
|
||||
|
||||
Start:
|
||||
|
||||
; Save the zero page locations we need
|
||||
; Save the zero-page locations that we need.
|
||||
|
||||
ldx #zpspace-1
|
||||
L1: lda sp,x
|
||||
@ -31,24 +31,24 @@ L1: lda sp,x
|
||||
dex
|
||||
bpl L1
|
||||
|
||||
; Switch to second charset
|
||||
; Switch to the second charset.
|
||||
|
||||
lda #14
|
||||
jsr BSOUT
|
||||
|
||||
; Switch off the BASIC ROM
|
||||
; Switch off the BASIC ROM.
|
||||
|
||||
lda $01
|
||||
pha ; Remember the value
|
||||
and #$F8
|
||||
ora #$06 ; Enable kernal+I/O, disable basic
|
||||
ora #$06 ; Enable Kernal+I/O, disable BASIC
|
||||
sta $01
|
||||
|
||||
; Clear the BSS data
|
||||
; Clear the BSS data.
|
||||
|
||||
jsr zerobss
|
||||
|
||||
; Save system settings and setup the stack
|
||||
; Save some system settings; and, set up the stack.
|
||||
|
||||
pla
|
||||
sta mmusave ; Save the memory configuration
|
||||
@ -61,20 +61,20 @@ L1: lda sp,x
|
||||
lda #>(__RAM_START__ + __RAM_SIZE__ + __STACKSIZE__)
|
||||
sta sp+1 ; Set argument stack ptr
|
||||
|
||||
; Call module constructors
|
||||
; Call the module constructors.
|
||||
|
||||
jsr initlib
|
||||
|
||||
; Push arguments and call main
|
||||
; Push the command-line arguments; and, call main().
|
||||
|
||||
jsr callmain
|
||||
|
||||
; Back from main (This is also the _exit entry). Run module destructors
|
||||
; Back from main() [this is also the exit() entry]. Run the module destructors.
|
||||
|
||||
_exit: pha ; Save the return code on stack
|
||||
jsr donelib
|
||||
|
||||
; Copy back the zero page stuff
|
||||
; Copy back the zero-page stuff.
|
||||
|
||||
ldx #zpspace-1
|
||||
L2: lda zpsave,x
|
||||
@ -82,19 +82,19 @@ L2: lda zpsave,x
|
||||
dex
|
||||
bpl L2
|
||||
|
||||
; Place the program return code into ST
|
||||
; Place the program return code into BASIC's status variable.
|
||||
|
||||
pla
|
||||
sta ST
|
||||
|
||||
; Restore system stuff
|
||||
; Restore the system stuff.
|
||||
|
||||
ldx spsave
|
||||
txs ; Restore stack pointer
|
||||
ldx mmusave
|
||||
stx $01 ; Restore memory configuration
|
||||
|
||||
; Back to basic
|
||||
; Back to BASIC.
|
||||
|
||||
rts
|
||||
|
||||
|
||||
@ -18,14 +18,14 @@
|
||||
|
||||
|
||||
; ------------------------------------------------------------------------
|
||||
; BASIC header and a small BASIC program. Since it is not possible to start
|
||||
; The BASIC header and a small BASIC program. Since it isn't possible to start
|
||||
; programs in other banks using SYS, the BASIC program will write a small
|
||||
; machine code program into memory at $100 and start that machine code
|
||||
; machine code program into memory at $100; and, start that machine code
|
||||
; program. The machine code program will then start the machine language
|
||||
; code in bank 0, which will initialize the system by copying stuff from
|
||||
; the system bank, and start the application.
|
||||
;
|
||||
; Here's the basic program that's in the following lines:
|
||||
; Here's the BASIC program that's in the following lines:
|
||||
;
|
||||
; 10 for i=0 to 4
|
||||
; 20 read j
|
||||
@ -40,9 +40,9 @@
|
||||
; lda #$00
|
||||
; sta $00 <-- Switch to bank 0 after this command
|
||||
;
|
||||
; Initialization is not only complex because of the jumping from one bank
|
||||
; into another. but also because we want to save memory, and because of
|
||||
; this, we will use the system memory ($00-$3FF) for initialization stuff
|
||||
; Initialization is complex not only because of the jumping from one bank
|
||||
; into another, but also because we want to save memory; and because of
|
||||
; that, we will use the system memory ($00-$3FF) for initialization stuff
|
||||
; that is overwritten later.
|
||||
;
|
||||
|
||||
@ -55,13 +55,15 @@
|
||||
.byte $30,$2c,$31,$36,$39,$2c,$30,$2c,$31,$33,$33,$2c,$30,$00,$00,$00
|
||||
|
||||
;------------------------------------------------------------------------------
|
||||
; A table that contains values that must be transfered from the system zero
|
||||
; page into our zero page. Contains pairs of bytes; first one is the address
|
||||
; in the system ZP, second one is our ZP address. The table goes into page 2,
|
||||
; but is declared here because it is needed earlier.
|
||||
; A table that contains values that must be transferred from the system zero-
|
||||
; page into our zero-page. Contains pairs of bytes; first one is the address
|
||||
; in the system ZP, second one is our ZP address. The table goes into page 2;
|
||||
; but, is declared here because it is needed earlier.
|
||||
|
||||
.SEGMENT "PAGE2"
|
||||
|
||||
; (We use .proc because we need both a label and a scope.)
|
||||
|
||||
.proc transfer_table
|
||||
|
||||
.byte $9F, DEVNUM
|
||||
@ -78,7 +80,7 @@
|
||||
; Page 3 data. This page contains the break vector and the bankswitch
|
||||
; subroutine that is copied into high memory on startup. The space occupied by
|
||||
; this routine will later be used for a copy of the bank 15 stack. It must be
|
||||
; saved, since we're going to destroy it when calling bank 15.
|
||||
; saved since we're going to destroy it when calling bank 15.
|
||||
|
||||
.segment "PAGE3"
|
||||
|
||||
@ -92,7 +94,7 @@ BRKVec: .addr _exit ; BRK indirect vector
|
||||
|
||||
entry: php
|
||||
pha
|
||||
lda #$0F ; Bank 15
|
||||
lda #$0F ; Bank 15
|
||||
sta IndReg
|
||||
txa
|
||||
pha
|
||||
@ -115,7 +117,7 @@ entry: php
|
||||
tya
|
||||
sec
|
||||
sbc #7
|
||||
sta $1FF ; Save new sp
|
||||
sta $1FF ; Save new sp
|
||||
tay
|
||||
|
||||
tsx
|
||||
@ -143,7 +145,7 @@ entry: php
|
||||
iny
|
||||
sta (sysp1),y
|
||||
|
||||
ldy $1FF ; Restore sp in bank 15
|
||||
ldy $1FF ; Restore sp in bank 15
|
||||
|
||||
lda #.hibyte(expull-1)
|
||||
sta (sysp1),y
|
||||
@ -170,7 +172,7 @@ expull: pla
|
||||
rts
|
||||
|
||||
.if (expull <> $FF26)
|
||||
.error "Symbol expull must be aligned with kernal in bank 15"
|
||||
.error "Symbol expull must be aligned with Kernal in bank 15"
|
||||
.endif
|
||||
|
||||
.reloc
|
||||
@ -180,15 +182,15 @@ expull: pla
|
||||
;------------------------------------------------------------------------------
|
||||
; The code in the target bank when switching back will be put at the bottom
|
||||
; of the stack. We will jump here to switch segments. The range $F2..$FF is
|
||||
; not used by any kernal routine.
|
||||
; not used by any Kernal routine.
|
||||
|
||||
.segment "STARTUP"
|
||||
|
||||
Back: sta ExecReg
|
||||
|
||||
; We are at $100 now. The following snippet is a copy of the code that is poked
|
||||
; in the system bank memory by the basic header program, it's only for
|
||||
; documentation and not actually used here:
|
||||
; in the system bank memory by the BASIC header program; it's only for
|
||||
; documentation, and not actually used here:
|
||||
|
||||
sei
|
||||
lda #$00
|
||||
@ -196,23 +198,23 @@ Back: sta ExecReg
|
||||
|
||||
; This is the actual starting point of our code after switching banks for
|
||||
; startup. Beware: The following code will get overwritten as soon as we
|
||||
; use the stack (since it's in page 1)! We jump to another location, since
|
||||
; use the stack (since it's in page 1)! We jump to another location since
|
||||
; we need some space for subroutines that aren't used later.
|
||||
|
||||
jmp Origin
|
||||
|
||||
; Hardware vectors, copied to $FFFA
|
||||
; Hardware vectors, copied to $FFF6
|
||||
|
||||
.proc vectors
|
||||
sta ExecReg
|
||||
rts
|
||||
nop
|
||||
.word nmi ; NMI vector
|
||||
.word 0 ; Reset - not used
|
||||
.word 0 ; Reset -- not used
|
||||
.word irq ; IRQ vector
|
||||
.endproc
|
||||
|
||||
; Initializers for the extended zeropage. See extzp.s
|
||||
; Initializers for the extended zero-page. See "extzp.s".
|
||||
|
||||
.proc extzp
|
||||
.word $0100 ; sysp1
|
||||
@ -230,12 +232,12 @@ Back: sta ExecReg
|
||||
.word $ebd1 ; ktab4
|
||||
.endproc
|
||||
|
||||
; Switch the indirect segment to the system bank
|
||||
; Switch the indirect segment to the system bank.
|
||||
|
||||
Origin: lda #$0F
|
||||
sta IndReg
|
||||
|
||||
; Initialize the extended zeropage
|
||||
; Initialize the extended zero-page.
|
||||
|
||||
ldx #.sizeof(extzp)-1
|
||||
L1: lda extzp,x
|
||||
@ -243,16 +245,16 @@ L1: lda extzp,x
|
||||
dex
|
||||
bpl L1
|
||||
|
||||
; Save the old stack pointer from the system bank and setup our hw sp
|
||||
; Save the old stack pointer from the system bank; and, set up our hw sp.
|
||||
|
||||
tsx
|
||||
txa
|
||||
ldy #$FF
|
||||
sta (sysp1),y ; Save system stack point into $F:$1FF
|
||||
ldx #$FE ; Leave $1FF untouched for cross bank calls
|
||||
ldx #$FE ; Leave $1FF untouched for cross-bank calls
|
||||
txs ; Set up our own stack
|
||||
|
||||
; Copy stuff from the system zeropage to ours
|
||||
; Copy stuff from the system zero-page to ours.
|
||||
|
||||
lda #.sizeof(transfer_table)
|
||||
sta ktmp
|
||||
@ -266,7 +268,7 @@ L2: ldx ktmp
|
||||
dec ktmp
|
||||
bne L2
|
||||
|
||||
; Set the interrupt, NMI and other vectors
|
||||
; Set the interrupt, NMI, and other vectors.
|
||||
|
||||
ldx #.sizeof(vectors)-1
|
||||
L3: lda vectors,x
|
||||
@ -274,14 +276,14 @@ L3: lda vectors,x
|
||||
dex
|
||||
bpl L3
|
||||
|
||||
; Setup the C stack
|
||||
; Set up the C stack.
|
||||
|
||||
lda #.lobyte(callbank15::entry)
|
||||
sta sp
|
||||
lda #.hibyte(callbank15::entry)
|
||||
sta sp+1
|
||||
|
||||
; Setup the subroutine and jump vector table that redirects kernal calls to
|
||||
; Set up the subroutine and jump vector table that redirects Kernal calls to
|
||||
; the system bank.
|
||||
|
||||
ldy #.sizeof(callbank15)
|
||||
@ -290,10 +292,10 @@ L3: lda vectors,x
|
||||
dey
|
||||
bne @L1
|
||||
|
||||
; Setup the jump vector table. Y is zero on entry.
|
||||
; Set up the jump vector table. Y is zero on entry.
|
||||
|
||||
ldx #45-1 ; Number of vectors
|
||||
@L2: lda #$20 ; JSR opcode
|
||||
ldx #45-1 ; Number of vectors
|
||||
@L2: lda #$20 ; JSR opcode
|
||||
sta $FF6F,y
|
||||
iny
|
||||
lda #.lobyte(callbank15::entry)
|
||||
@ -305,13 +307,13 @@ L3: lda vectors,x
|
||||
dex
|
||||
bpl @L2
|
||||
|
||||
; Set the indirect segment to bank we're executing in
|
||||
; Set the indirect segment to the bank that we're executing in.
|
||||
|
||||
lda ExecReg
|
||||
sta IndReg
|
||||
|
||||
; Zero the BSS segment. We will do that here instead calling the routine
|
||||
; in the common library, since we have the memory anyway, and this way,
|
||||
; Zero the BSS segment. We will do that here instead of calling the routine
|
||||
; in the common library, since we have the memory anyway; and this way,
|
||||
; it's reused later.
|
||||
|
||||
lda #<__BSS_RUN__
|
||||
@ -321,18 +323,18 @@ L3: lda vectors,x
|
||||
lda #0
|
||||
tay
|
||||
|
||||
; Clear full pages
|
||||
; Clear full pages.
|
||||
|
||||
ldx #>__BSS_SIZE__
|
||||
beq Z2
|
||||
Z1: sta (ptr1),y
|
||||
iny
|
||||
bne Z1
|
||||
inc ptr1+1 ; Next page
|
||||
inc ptr1+1 ; Next page
|
||||
dex
|
||||
bne Z1
|
||||
|
||||
; Clear the remaining page
|
||||
; Clear the remaining page.
|
||||
|
||||
Z2: ldx #<__BSS_SIZE__
|
||||
beq Z4
|
||||
@ -343,12 +345,12 @@ Z3: sta (ptr1),y
|
||||
Z4: jmp Init
|
||||
|
||||
; ------------------------------------------------------------------------
|
||||
; We are at $200 now. We may now start calling subroutines safely, since
|
||||
; We are at $200 now. We may now start calling subroutines safely since
|
||||
; the code we execute is no longer in the stack page.
|
||||
|
||||
.segment "PAGE2"
|
||||
|
||||
; Copy the character rom from the system bank into the execution bank
|
||||
; Copy the character ROM from the system bank into the execution bank.
|
||||
|
||||
Init: lda #<$C000
|
||||
sta ptr1
|
||||
@ -362,7 +364,7 @@ Init: lda #<$C000
|
||||
sta tmp1
|
||||
ldy #$00
|
||||
ccopy: lda #$0F
|
||||
sta IndReg ; Access the system bank
|
||||
sta IndReg ; Access the system bank
|
||||
ccopy1: lda (ptr1),y
|
||||
sta __VIDRAM_START__,y
|
||||
iny
|
||||
@ -374,22 +376,22 @@ ccopy2: lda __VIDRAM_START__,y
|
||||
iny
|
||||
bne ccopy2
|
||||
inc ptr1+1
|
||||
inc ptr2+1 ; Bump high pointer bytes
|
||||
inc ptr2+1 ; Bump high pointer bytes
|
||||
dec tmp1
|
||||
bne ccopy
|
||||
|
||||
; Clear the video memory. We will do this before switching the video to bank 0
|
||||
; Clear the video memory. We will do this before switching the video to bank 0,
|
||||
; to avoid garbage when doing so.
|
||||
|
||||
jsr _clrscr
|
||||
|
||||
; Reprogram the VIC so that the text screen and the character ROM is in the
|
||||
; Reprogram the VIC so that the text screen and the character ROM are in the
|
||||
; execution bank. This is done in three steps:
|
||||
|
||||
lda #$0F ; We need access to the system bank
|
||||
lda #$0F ; We need access to the system bank
|
||||
sta IndReg
|
||||
|
||||
; Place the VIC video RAM into bank 0
|
||||
; Place the VIC video RAM into bank 0.
|
||||
; CA (STATVID) = 0
|
||||
; CB (VICDOTSEL) = 0
|
||||
|
||||
@ -400,7 +402,7 @@ ccopy2: lda __VIDRAM_START__,y
|
||||
ora #%10100000
|
||||
sta (tpi1),y
|
||||
|
||||
; Set bit 14/15 of the VIC address range to the high bits of __VIDRAM_START__
|
||||
; Set bit 14/15 of the VIC address range to the high bits of __VIDRAM_START__.
|
||||
; PC6/PC7 (VICBANKSEL 0/1) = 11
|
||||
|
||||
ldy #TPI::PRC
|
||||
@ -422,12 +424,12 @@ ccopy2: lda __VIDRAM_START__,y
|
||||
; ora #<(((>__VIDRAM_START__) << 2) & $F0)
|
||||
sta (vic),y
|
||||
|
||||
; Switch back to the execution bank
|
||||
; Switch back to the execution bank.
|
||||
|
||||
lda ExecReg
|
||||
sta IndReg
|
||||
|
||||
; Activate chained interrupt handlers, then enable interrupts.
|
||||
; Activate the chained interrupt handlers; then, enable interrupts.
|
||||
|
||||
lda #.lobyte(__INTERRUPTOR_COUNT__*2)
|
||||
sta irqcount
|
||||
@ -437,11 +439,11 @@ ccopy2: lda __VIDRAM_START__,y
|
||||
|
||||
jsr initlib
|
||||
|
||||
; Push arguments and call main()
|
||||
; Push the command-line arguments; and, call main().
|
||||
|
||||
jsr callmain
|
||||
|
||||
; Call module destructors. This is also the _exit entry and the default entry
|
||||
; Call the module destructors. This is also the exit() entry and the default entry
|
||||
; point for the break vector.
|
||||
|
||||
_exit: pha ; Save the return code on stack
|
||||
@ -449,12 +451,12 @@ _exit: pha ; Save the return code on stack
|
||||
lda #$00
|
||||
sta irqcount ; Disable custom irq handlers
|
||||
|
||||
; Address the system bank
|
||||
; Address the system bank.
|
||||
|
||||
lda #$0F
|
||||
sta IndReg
|
||||
|
||||
; Switch back the video to the system bank
|
||||
; Switch back the video to the system bank.
|
||||
|
||||
ldy #TPI::CR
|
||||
lda vidsave+0
|
||||
@ -468,7 +470,7 @@ _exit: pha ; Save the return code on stack
|
||||
lda vidsave+2
|
||||
sta (vic),y
|
||||
|
||||
; Copy stuff back from our zeropage to the systems
|
||||
; Copy stuff back from our zero-page to the system's.
|
||||
|
||||
.if 0
|
||||
lda #.sizeof(transfer_table)
|
||||
@ -484,13 +486,13 @@ _exit: pha ; Save the return code on stack
|
||||
bne @L0
|
||||
.endif
|
||||
|
||||
; Place the program return code into ST
|
||||
; Place the program return code into BASIC's status variable.
|
||||
|
||||
pla
|
||||
ldy #$9C ; ST
|
||||
sta (sysp0),y
|
||||
|
||||
; Setup the welcome code at the stack bottom in the system bank.
|
||||
; Set up the welcome code at the stack bottom in the system bank.
|
||||
|
||||
ldy #$FF
|
||||
lda (sysp1),y ; Load system bank sp
|
||||
@ -511,14 +513,14 @@ _exit: pha ; Save the return code on stack
|
||||
; easier chaining, we do handle the IRQs in the execution bank (instead of
|
||||
; passing them to the system bank).
|
||||
|
||||
; This is the mapping of the active irq register of the 6525 (tpi1):
|
||||
; This is the mapping of the active IRQ register of the 6525 (tpi1):
|
||||
;
|
||||
; Bit 7 6 5 4 3 2 1 0
|
||||
; | | | | ^ 50 Hz
|
||||
; | | | | ^ 50 Hz.
|
||||
; | | | ^ SRQ IEEE 488
|
||||
; | | ^ cia
|
||||
; | | ^ CIA
|
||||
; | ^ IRQB ext. Port
|
||||
; ^ acia
|
||||
; ^ ACIA
|
||||
|
||||
irq: pha
|
||||
txa
|
||||
@ -528,41 +530,41 @@ irq: pha
|
||||
lda IndReg
|
||||
pha
|
||||
lda ExecReg
|
||||
sta IndReg ; Be sure to address our segment
|
||||
sta IndReg ; Be sure to address our segment
|
||||
tsx
|
||||
lda $105,x ; Get the flags from the stack
|
||||
and #$10 ; Test break flag
|
||||
lda $105,x ; Get the flags from the stack
|
||||
and #$10 ; Test break flag
|
||||
bne dobrk
|
||||
|
||||
; It's an IRQ
|
||||
; It's an IRQ.
|
||||
|
||||
cld
|
||||
|
||||
; Call chained IRQ handlers
|
||||
; Call the chained IRQ handlers.
|
||||
|
||||
ldy irqcount
|
||||
beq irqskip
|
||||
jsr callirq_y ; Call the functions
|
||||
jsr callirq_y ; Call the functions
|
||||
|
||||
; Done with chained IRQ handlers, check the TPI for IRQs and handle them
|
||||
; Done with the chained IRQ handlers; check the TPI for IRQs, and handle them.
|
||||
|
||||
irqskip:lda #$0F
|
||||
sta IndReg
|
||||
ldy #TPI::AIR
|
||||
lda (tpi1),y ; Interrupt Register 6525
|
||||
lda (tpi1),y ; Interrupt Register 6525
|
||||
beq noirq
|
||||
|
||||
; 50/60Hz interrupt
|
||||
; 50/60Hz. interrupt
|
||||
|
||||
cmp #%00000001 ; ticker irq?
|
||||
cmp #%00000001 ; ticker IRQ?
|
||||
bne irqend
|
||||
jsr scnkey ; Poll the keyboard
|
||||
jsr UDTIM ; Bump the time
|
||||
jsr scnkey ; Poll the keyboard
|
||||
jsr UDTIM ; Bump the time
|
||||
|
||||
; Done
|
||||
; Done.
|
||||
|
||||
irqend: ldy #TPI::AIR
|
||||
sta (tpi1),y ; Clear interrupt
|
||||
sta (tpi1),y ; Clear interrupt
|
||||
|
||||
noirq: pla
|
||||
sta IndReg
|
||||
@ -583,5 +585,3 @@ vidsave:.res 3
|
||||
|
||||
.bss
|
||||
irqcount: .byte 0
|
||||
|
||||
|
||||
|
||||
@ -17,14 +17,14 @@
|
||||
|
||||
|
||||
; ------------------------------------------------------------------------
|
||||
; BASIC header and a small BASIC program. Since it is not possible to start
|
||||
; The BASIC header and a small BASIC program. Since it isn't possible to start
|
||||
; programs in other banks using SYS, the BASIC program will write a small
|
||||
; machine code program into memory at $100 and start that machine code
|
||||
; machine code program into memory at $100; and, start that machine code
|
||||
; program. The machine code program will then start the machine language
|
||||
; code in bank 1, which will initialize the system by copying stuff from
|
||||
; the system bank, and start the application.
|
||||
;
|
||||
; Here's the basic program that's in the following lines:
|
||||
; Here's the BASIC program that's in the following lines:
|
||||
;
|
||||
; 10 for i=0 to 4
|
||||
; 20 read j
|
||||
@ -39,9 +39,9 @@
|
||||
; lda #$01
|
||||
; sta $00 <-- Switch to bank 1 after this command
|
||||
;
|
||||
; Initialization is not only complex because of the jumping from one bank
|
||||
; into another. but also because we want to save memory, and because of
|
||||
; this, we will use the system memory ($00-$3FF) for initialization stuff
|
||||
; Initialization is complex not only because of the jumping from one bank
|
||||
; into another. but also because we want to save memory; and because of
|
||||
; that, we will use the system memory ($00-$3FF) for initialization stuff
|
||||
; that is overwritten later.
|
||||
;
|
||||
|
||||
@ -54,13 +54,15 @@
|
||||
.byte $30,$2c,$31,$36,$39,$2c,$31,$2c,$31,$33,$33,$2c,$30,$00,$00,$00
|
||||
|
||||
;------------------------------------------------------------------------------
|
||||
; A table that contains values that must be transfered from the system zero
|
||||
; page into out zero page. Contains pairs of bytes, first one is the address
|
||||
; in the system ZP, second one is our ZP address. The table goes into page 2,
|
||||
; but is declared here, because it is needed earlier.
|
||||
; A table that contains values that must be transferred from the system zero-
|
||||
; page into our zero-page. Contains pairs of bytes, first one is the address
|
||||
; in the system ZP, second one is our ZP address. The table goes into page 2;
|
||||
; but, is declared here because it is needed earlier.
|
||||
|
||||
.SEGMENT "PAGE2"
|
||||
|
||||
; (We use .proc because we need both a label and a scope.)
|
||||
|
||||
.proc transfer_table
|
||||
|
||||
.byte $9F, DEVNUM
|
||||
@ -76,7 +78,7 @@
|
||||
; Page 3 data. This page contains the break vector and the bankswitch
|
||||
; subroutine that is copied into high memory on startup. The space occupied by
|
||||
; this routine will later be used for a copy of the bank 15 stack. It must be
|
||||
; saved, since we're going to destroy it when calling bank 15.
|
||||
; saved since we're going to destroy it when calling bank 15.
|
||||
|
||||
.segment "PAGE3"
|
||||
|
||||
@ -84,13 +86,13 @@ BRKVec: .addr _exit ; BRK indirect vector
|
||||
|
||||
.proc callbank15
|
||||
|
||||
excrts := $FF05 ; In bank 15 rom
|
||||
excrts := $FF05 ; In bank 15 ROM
|
||||
|
||||
.org $FECB
|
||||
|
||||
entry: php
|
||||
pha
|
||||
lda #$0F ; Bank 15
|
||||
lda #$0F ; Bank 15
|
||||
sta IndReg
|
||||
txa
|
||||
pha
|
||||
@ -113,7 +115,7 @@ entry: php
|
||||
tya
|
||||
sec
|
||||
sbc #7
|
||||
sta $1FF ; Save new sp
|
||||
sta $1FF ; Save new sp
|
||||
tay
|
||||
|
||||
tsx
|
||||
@ -141,7 +143,7 @@ entry: php
|
||||
iny
|
||||
sta (sysp1),y
|
||||
|
||||
ldy $1FF ; Restore sp in bank 15
|
||||
ldy $1FF ; Restore sp in bank 15
|
||||
|
||||
lda #.hibyte(expull-1)
|
||||
sta (sysp1),y
|
||||
@ -168,7 +170,7 @@ expull: pla
|
||||
rts
|
||||
|
||||
.if (expull <> $FF2E)
|
||||
.error "Symbol expull must be aligned with kernal in bank 15"
|
||||
.error "Symbol expull must be aligned with Kernal in bank 15"
|
||||
.endif
|
||||
|
||||
.reloc
|
||||
@ -178,15 +180,15 @@ expull: pla
|
||||
;------------------------------------------------------------------------------
|
||||
; The code in the target bank when switching back will be put at the bottom
|
||||
; of the stack. We will jump here to switch segments. The range $F2..$FF is
|
||||
; not used by any kernal routine.
|
||||
; not used by any Kernal routine.
|
||||
|
||||
.segment "STARTUP"
|
||||
|
||||
Back: sta ExecReg
|
||||
|
||||
; We are at $100 now. The following snippet is a copy of the code that is poked
|
||||
; in the system bank memory by the basic header program, it's only for
|
||||
; documentation and not actually used here:
|
||||
; in the system bank memory by the BASIC header program; it's only for
|
||||
; documentation, and not actually used here:
|
||||
|
||||
sei
|
||||
lda #$01
|
||||
@ -194,7 +196,7 @@ Back: sta ExecReg
|
||||
|
||||
; This is the actual starting point of our code after switching banks for
|
||||
; startup. Beware: The following code will get overwritten as soon as we
|
||||
; use the stack (since it's in page 1)! We jump to another location, since
|
||||
; use the stack (since it's in page 1)! We jump to another location since
|
||||
; we need some space for subroutines that aren't used later.
|
||||
|
||||
jmp Origin
|
||||
@ -206,11 +208,11 @@ Back: sta ExecReg
|
||||
rts
|
||||
nop
|
||||
.word nmi ; NMI vector
|
||||
.word 0 ; Reset - not used
|
||||
.word 0 ; Reset -- not used
|
||||
.word irq ; IRQ vector
|
||||
.endproc
|
||||
|
||||
; Initializers for the extended zeropage. See extzp.s
|
||||
; Initializers for the extended zero-page. See "extzp.s".
|
||||
|
||||
.proc extzp
|
||||
.word $0100 ; sysp1
|
||||
@ -228,12 +230,12 @@ Back: sta ExecReg
|
||||
.word $eb49 ; ktab4
|
||||
.endproc
|
||||
|
||||
; Switch the indirect segment to the system bank
|
||||
; Switch the indirect segment to the system bank.
|
||||
|
||||
Origin: lda #$0F
|
||||
sta IndReg
|
||||
|
||||
; Initialize the extended zeropage
|
||||
; Initialize the extended zero-page.
|
||||
|
||||
ldx #.sizeof(extzp)-1
|
||||
L1: lda extzp,x
|
||||
@ -241,16 +243,16 @@ L1: lda extzp,x
|
||||
dex
|
||||
bpl L1
|
||||
|
||||
; Save the old stack pointer from the system bank and setup our hw sp
|
||||
; Save the old stack pointer from the system bank; and, set up our hw sp.
|
||||
|
||||
tsx
|
||||
txa
|
||||
ldy #$FF
|
||||
sta (sysp1),y ; Save system stack point into $F:$1FF
|
||||
ldx #$FE ; Leave $1FF untouched for cross bank calls
|
||||
ldx #$FE ; Leave $1FF untouched for cross-bank calls
|
||||
txs ; Set up our own stack
|
||||
|
||||
; Copy stuff from the system zeropage to ours
|
||||
; Copy stuff from the system zero-page to ours.
|
||||
|
||||
lda #.sizeof(transfer_table)
|
||||
sta ktmp
|
||||
@ -264,7 +266,7 @@ L2: ldx ktmp
|
||||
dec ktmp
|
||||
bne L2
|
||||
|
||||
; Set the interrupt, NMI and other vectors
|
||||
; Set the interrupt, NMI, and other vectors.
|
||||
|
||||
ldx #.sizeof(vectors)-1
|
||||
L3: lda vectors,x
|
||||
@ -272,14 +274,14 @@ L3: lda vectors,x
|
||||
dex
|
||||
bpl L3
|
||||
|
||||
; Setup the C stack
|
||||
; Set up the C stack.
|
||||
|
||||
lda #.lobyte(callbank15::entry)
|
||||
sta sp
|
||||
lda #.hibyte(callbank15::entry)
|
||||
sta sp+1
|
||||
|
||||
; Setup the subroutine and jump vector table that redirects kernal calls to
|
||||
; Set up the subroutine and jump vector table that redirects Kernal calls to
|
||||
; the system bank.
|
||||
|
||||
ldy #.sizeof(callbank15)
|
||||
@ -288,10 +290,10 @@ L3: lda vectors,x
|
||||
dey
|
||||
bne @L1
|
||||
|
||||
; Setup the jump vector table. Y is zero on entry.
|
||||
; Set up the jump vector table. Y is zero on entry.
|
||||
|
||||
ldx #45-1 ; Number of vectors
|
||||
@L2: lda #$20 ; JSR opcode
|
||||
ldx #45-1 ; Number of vectors
|
||||
@L2: lda #$20 ; JSR opcode
|
||||
sta $FF6F,y
|
||||
iny
|
||||
lda #.lobyte(callbank15::entry)
|
||||
@ -303,13 +305,13 @@ L3: lda vectors,x
|
||||
dex
|
||||
bpl @L2
|
||||
|
||||
; Set the indirect segment to bank we're executing in
|
||||
; Set the indirect segment to the bank that we're executing in.
|
||||
|
||||
lda ExecReg
|
||||
sta IndReg
|
||||
|
||||
; Zero the BSS segment. We will do that here instead calling the routine
|
||||
; in the common library, since we have the memory anyway, and this way,
|
||||
; Zero the BSS segment. We will do that here instead of calling the routine
|
||||
; in the common library, since we have the memory anyway; and this way,
|
||||
; it's reused later.
|
||||
|
||||
lda #<__BSS_RUN__
|
||||
@ -319,18 +321,18 @@ L3: lda vectors,x
|
||||
lda #0
|
||||
tay
|
||||
|
||||
; Clear full pages
|
||||
; Clear full pages.
|
||||
|
||||
ldx #>__BSS_SIZE__
|
||||
beq Z2
|
||||
Z1: sta (ptr1),y
|
||||
iny
|
||||
bne Z1
|
||||
inc ptr1+1 ; Next page
|
||||
inc ptr1+1 ; Next page
|
||||
dex
|
||||
bne Z1
|
||||
|
||||
; Clear the remaining page
|
||||
; Clear the remaining page.
|
||||
|
||||
Z2: ldx #<__BSS_SIZE__
|
||||
beq Z4
|
||||
@ -341,12 +343,12 @@ Z3: sta (ptr1),y
|
||||
Z4: jmp Init
|
||||
|
||||
; ------------------------------------------------------------------------
|
||||
; We are at $200 now. We may now start calling subroutines safely, since
|
||||
; We are at $200 now. We may now start calling subroutines safely since
|
||||
; the code we execute is no longer in the stack page.
|
||||
|
||||
.segment "PAGE2"
|
||||
|
||||
; Activate chained interrupt handlers, then enable interrupts.
|
||||
; Activate the chained interrupt handlers; then, enable interrupts.
|
||||
|
||||
Init: lda #.lobyte(__INTERRUPTOR_COUNT__*2)
|
||||
sta irqcount
|
||||
@ -356,11 +358,11 @@ Init: lda #.lobyte(__INTERRUPTOR_COUNT__*2)
|
||||
|
||||
jsr initlib
|
||||
|
||||
; Push arguments and call main()
|
||||
; Push the command-line arguments; and, call main().
|
||||
|
||||
jsr callmain
|
||||
|
||||
; Call module destructors. This is also the _exit entry and the default entry
|
||||
; Call the module destructors. This is also the exit() entry and the default entry
|
||||
; point for the break vector.
|
||||
|
||||
_exit: pha ; Save the return code
|
||||
@ -368,12 +370,12 @@ _exit: pha ; Save the return code
|
||||
lda #$00
|
||||
sta irqcount ; Disable custom irq handlers
|
||||
|
||||
; Address the system bank
|
||||
; Address the system bank.
|
||||
|
||||
lda #$0F
|
||||
sta IndReg
|
||||
|
||||
; Copy stuff back from our zeropage to the systems
|
||||
; Copy stuff back from our zero-page to the system's.
|
||||
|
||||
.if 0
|
||||
lda #.sizeof(transfer_table)
|
||||
@ -389,13 +391,13 @@ _exit: pha ; Save the return code
|
||||
bne @L0
|
||||
.endif
|
||||
|
||||
; Place the program return code into ST
|
||||
; Place the program return code into BASIC's status variable.
|
||||
|
||||
pla
|
||||
ldy #$9C ; ST
|
||||
sta (sysp0),y
|
||||
|
||||
; Setup the welcome code at the stack bottom in the system bank.
|
||||
; Set up the welcome code at the stack bottom in the system bank.
|
||||
|
||||
ldy #$FF
|
||||
lda (sysp1),y ; Load system bank sp
|
||||
@ -416,14 +418,14 @@ _exit: pha ; Save the return code
|
||||
; easier chaining, we do handle the IRQs in the execution bank (instead of
|
||||
; passing them to the system bank).
|
||||
|
||||
; This is the mapping of the active irq register of the 6525 (tpi1):
|
||||
; This is the mapping of the active IRQ register of the 6525 (tpi1):
|
||||
;
|
||||
; Bit 7 6 5 4 3 2 1 0
|
||||
; | | | | ^ 50 Hz
|
||||
; | | | | ^ 50 Hz.
|
||||
; | | | ^ SRQ IEEE 488
|
||||
; | | ^ cia
|
||||
; | | ^ CIA
|
||||
; | ^ IRQB ext. Port
|
||||
; ^ acia
|
||||
; ^ ACIA
|
||||
|
||||
irq: pha
|
||||
txa
|
||||
@ -433,41 +435,41 @@ irq: pha
|
||||
lda IndReg
|
||||
pha
|
||||
lda ExecReg
|
||||
sta IndReg ; Be sure to address our segment
|
||||
sta IndReg ; Be sure to address our segment
|
||||
tsx
|
||||
lda $105,x ; Get the flags from the stack
|
||||
and #$10 ; Test break flag
|
||||
lda $105,x ; Get the flags from the stack
|
||||
and #$10 ; Test break flag
|
||||
bne dobrk
|
||||
|
||||
; It's an IRQ
|
||||
; It's an IRQ.
|
||||
|
||||
cld
|
||||
|
||||
; Call chained IRQ handlers
|
||||
; Call the chained IRQ handlers.
|
||||
|
||||
ldy irqcount
|
||||
beq irqskip
|
||||
jsr callirq_y ; Call the functions
|
||||
jsr callirq_y ; Call the functions
|
||||
|
||||
; Done with chained IRQ handlers, check the TPI for IRQs and handle them
|
||||
; Done with the chained IRQ handlers; check the TPI for IRQs, and handle them.
|
||||
|
||||
irqskip:lda #$0F
|
||||
sta IndReg
|
||||
ldy #TPI::AIR
|
||||
lda (tpi1),y ; Interrupt Register 6525
|
||||
lda (tpi1),y ; Interrupt Register 6525
|
||||
beq noirq
|
||||
|
||||
; 50/60Hz interrupt
|
||||
; 50/60Hz. interrupt
|
||||
|
||||
cmp #%00000001 ; ticker irq?
|
||||
cmp #%00000001 ; ticker IRQ?
|
||||
bne irqend
|
||||
jsr scnkey ; Poll the keyboard
|
||||
jsr UDTIM ; Bump the time
|
||||
jsr scnkey ; Poll the keyboard
|
||||
jsr UDTIM ; Bump the time
|
||||
|
||||
; Done
|
||||
; Done.
|
||||
|
||||
irqend: ldy #TPI::AIR
|
||||
sta (tpi1),y ; Clear interrupt
|
||||
sta (tpi1),y ; Clear interrupt
|
||||
|
||||
noirq: pla
|
||||
sta IndReg
|
||||
@ -481,8 +483,7 @@ nmi: rti
|
||||
dobrk: jmp (BRKVec)
|
||||
|
||||
; -------------------------------------------------------------------------
|
||||
; Data area.
|
||||
; Data area
|
||||
|
||||
.bss
|
||||
irqcount: .byte 0
|
||||
|
||||
|
||||
@ -1,5 +1,5 @@
|
||||
;
|
||||
; Startup code for geos
|
||||
; Startup code for GEOS
|
||||
;
|
||||
; Maciej 'YTM/Elysium' Witkowiak
|
||||
; 26.10.99, 10.3.2000, 15.8.2001, 23.12.2002
|
||||
@ -23,9 +23,9 @@
|
||||
.segment "STARTUP"
|
||||
|
||||
; GEOS 64/128 initializes the screen before starting an application while
|
||||
; Apple GEOS does not. In order to provide identical startup conditions
|
||||
; we initialize the screen here on Apple GEOS. For the same reason we set
|
||||
; the pattern and dispBufferOn even on GEOS 64/128 although we don't use
|
||||
; Apple GEOS does not. In order to provide identical startup conditions,
|
||||
; we initialize the screen here, on Apple GEOS. For the same reason, we set
|
||||
; the pattern and dispBufferOn, even on GEOS 64/128, although we don't use
|
||||
; them here.
|
||||
|
||||
lda #2 ; Checkerboard pattern
|
||||
@ -44,23 +44,23 @@
|
||||
|
||||
jsr zerobss
|
||||
|
||||
; Setup stack.
|
||||
; Set up the stack.
|
||||
|
||||
lda #<(__STACKADDR__ + __STACKSIZE__)
|
||||
ldx #>(__STACKADDR__ + __STACKSIZE__)
|
||||
sta sp
|
||||
stx sp+1
|
||||
|
||||
; Call module constructors.
|
||||
; Call the module constructors.
|
||||
|
||||
jsr initlib
|
||||
|
||||
; Push arguments and call main().
|
||||
; Push the command-line arguments; and, call main().
|
||||
|
||||
cli
|
||||
jsr callmain
|
||||
|
||||
; Call module destructors.
|
||||
; Call the module destructors.
|
||||
|
||||
_exit: jsr donelib
|
||||
|
||||
|
||||
@ -9,9 +9,9 @@
|
||||
;
|
||||
; ***
|
||||
;
|
||||
; Startup code for cc65 (Lynx version). Based on Atari 8-bit startup
|
||||
; Startup code for cc65 (Lynx version). Based on the Atari 8-bit startup
|
||||
; code structure. The C stack is located at the end of the RAM memory
|
||||
; segment and grows downward. Bastian Schick's executable header is put
|
||||
; segment, and grows downward. Bastian Schick's executable header is put
|
||||
; on the front of the fully linked binary (see EXEHDR segment.)
|
||||
;
|
||||
|
||||
@ -44,19 +44,19 @@ MikeyInitData: .byte $9e,$18,$68,$1f,$00,$00,$00,$00,$00,$ff,$1a,$1b,$04,$0d,$2
|
||||
|
||||
.segment "STARTUP"
|
||||
|
||||
; set up system
|
||||
; Set up the system.
|
||||
|
||||
sei
|
||||
cld
|
||||
ldx #$FF
|
||||
txs
|
||||
|
||||
; init bank switching
|
||||
; Init the bank switching.
|
||||
|
||||
lda #$C
|
||||
sta MAPCTL ; $FFF9
|
||||
|
||||
; disable all timer interrupts
|
||||
; Disable all timer interrupts.
|
||||
|
||||
lda #$80
|
||||
trb TIM0CTLA
|
||||
@ -67,24 +67,24 @@ MikeyInitData: .byte $9e,$18,$68,$1f,$00,$00,$00,$00,$00,$ff,$1a,$1b,$04,$0d,$2
|
||||
trb TIM6CTLA
|
||||
trb TIM7CTLA
|
||||
|
||||
; disable TX/RX IRQ, set to 8E1
|
||||
; Disable the TX/RX IRQ; set to 8E1.
|
||||
|
||||
lda #%11101
|
||||
sta SERCTL
|
||||
|
||||
; clear all pending interrupts
|
||||
; Clear all pending interrupts.
|
||||
|
||||
lda INTSET
|
||||
sta INTRST
|
||||
|
||||
; setup the stack
|
||||
; Set up the stack.
|
||||
|
||||
lda #<(__RAM_START__ + __RAM_SIZE__ + __STACKSIZE__)
|
||||
sta sp
|
||||
lda #>(__RAM_START__ + __RAM_SIZE__ + __STACKSIZE__)
|
||||
sta sp+1
|
||||
|
||||
; Init Mickey
|
||||
; Init Mickey.
|
||||
|
||||
ldx #.sizeof(MikeyInitReg)-1
|
||||
mloop: ldy MikeyInitReg,x
|
||||
@ -93,7 +93,7 @@ mloop: ldy MikeyInitReg,x
|
||||
dex
|
||||
bpl mloop
|
||||
|
||||
; these are RAM-shadows of read only regs
|
||||
; These are RAM-shadows of read-only regs.
|
||||
|
||||
ldx #$1b
|
||||
stx __iodat
|
||||
@ -102,7 +102,7 @@ mloop: ldy MikeyInitReg,x
|
||||
ldx #$d
|
||||
stx __viddma
|
||||
|
||||
; Init Suzy
|
||||
; Init Suzy.
|
||||
|
||||
ldx #.sizeof(SuzyInitReg)-1
|
||||
sloop: ldy SuzyInitReg,x
|
||||
@ -115,19 +115,19 @@ sloop: ldy SuzyInitReg,x
|
||||
sta __sprsys
|
||||
cli
|
||||
|
||||
; Clear the BSS data
|
||||
; Clear the BSS data.
|
||||
|
||||
jsr zerobss
|
||||
|
||||
; Call module constructors
|
||||
; Call the module constructors.
|
||||
|
||||
jsr initlib
|
||||
|
||||
; Push arguments and call main
|
||||
; Push the command-line arguments; and, call main().
|
||||
|
||||
jsr callmain
|
||||
|
||||
; Call module destructors. This is also the _exit entry.
|
||||
; Call the module destructors. This is also the exit() entry.
|
||||
|
||||
_exit: jsr donelib ; Run module destructors
|
||||
|
||||
|
||||
@ -70,7 +70,7 @@
|
||||
|
||||
start:
|
||||
|
||||
; setup the CPU and System-IRQ
|
||||
; Set up the CPU and System-IRQ.
|
||||
|
||||
sei
|
||||
cld
|
||||
@ -90,40 +90,40 @@ start:
|
||||
inx
|
||||
bne @l
|
||||
|
||||
; Clear the BSS data
|
||||
; Clear the BSS data.
|
||||
|
||||
jsr zerobss
|
||||
|
||||
; initialize data
|
||||
; Initialize the data.
|
||||
jsr copydata
|
||||
|
||||
; setup the stack
|
||||
; Set up the stack.
|
||||
|
||||
lda #<(__SRAM_START__ + __SRAM_SIZE__)
|
||||
sta sp
|
||||
lda #>(__SRAM_START__ + __SRAM_SIZE__)
|
||||
sta sp+1 ; Set argument stack ptr
|
||||
|
||||
; Call module constructors
|
||||
; Call the module constructors.
|
||||
|
||||
jsr initlib
|
||||
|
||||
; Push arguments and call main()
|
||||
; Push the command-line arguments; and, call main().
|
||||
|
||||
jsr callmain
|
||||
|
||||
; Call module destructors. This is also the _exit entry.
|
||||
; Call the module destructors. This is also the exit() entry.
|
||||
|
||||
_exit: jsr donelib ; Run module destructors
|
||||
|
||||
; Reset the NES
|
||||
; Reset the NES.
|
||||
|
||||
jmp start
|
||||
|
||||
; ------------------------------------------------------------------------
|
||||
; System V-Blank Interupt
|
||||
; updates PPU Memory (buffered)
|
||||
; updates VBLANK_FLAG and tickcount
|
||||
; System V-Blank Interrupt
|
||||
; Updates PPU Memory (buffered).
|
||||
; Updates VBLANK_FLAG and tickcount.
|
||||
; ------------------------------------------------------------------------
|
||||
|
||||
nmi: pha
|
||||
@ -141,13 +141,13 @@ nmi: pha
|
||||
|
||||
@s: jsr ppubuf_flush
|
||||
|
||||
; reset the video counter
|
||||
; Reset the video counter.
|
||||
lda #$20
|
||||
sta PPU_VRAM_ADDR2
|
||||
lda #$00
|
||||
sta PPU_VRAM_ADDR2
|
||||
|
||||
; reset scrolling
|
||||
; Reset scrolling.
|
||||
sta PPU_VRAM_ADDR1
|
||||
sta PPU_VRAM_ADDR1
|
||||
|
||||
|
||||
@ -21,7 +21,7 @@
|
||||
|
||||
Start:
|
||||
|
||||
; Save the zero page locations we need
|
||||
; Save the zero-page locations that we need.
|
||||
|
||||
ldx #zpspace-1
|
||||
L1: lda sp,x
|
||||
@ -29,9 +29,9 @@ L1: lda sp,x
|
||||
dex
|
||||
bpl L1
|
||||
|
||||
; Switch to second charset. The routine that is called by BSOUT to switch the
|
||||
; character set will use FNLEN as temporary storage - YUCK! Since the
|
||||
; initmainargs routine, which parses the command line for arguments needs this
|
||||
; Switch to the second charset. The routine that is called by BSOUT to switch the
|
||||
; character set will use FNLEN as temporary storage -- YUCK! Since the
|
||||
; initmainargs routine, which parses the command line for arguments, needs that
|
||||
; information, we need to save and restore it here.
|
||||
; Thanks to Stefan Haubenthal for this information!
|
||||
|
||||
@ -43,11 +43,11 @@ L1: lda sp,x
|
||||
pla
|
||||
sta FNLEN ; Restore FNLEN
|
||||
|
||||
; Clear the BSS data
|
||||
; Clear the BSS data.
|
||||
|
||||
jsr zerobss
|
||||
|
||||
; Save system stuff and setup the stack
|
||||
; Save some system stuff; and, set up the stack.
|
||||
|
||||
tsx
|
||||
stx spsave ; Save the system stack ptr
|
||||
@ -57,20 +57,20 @@ L1: lda sp,x
|
||||
lda MEMSIZE+1
|
||||
sta sp+1 ; Set argument stack ptr
|
||||
|
||||
; Call module constructors
|
||||
; Call the module constructors.
|
||||
|
||||
jsr initlib
|
||||
|
||||
; Push arguments and call main()
|
||||
; Push the command-line arguments; and, call main().
|
||||
|
||||
jsr callmain
|
||||
|
||||
; Call module destructors. This is also the _exit entry.
|
||||
; Call the module destructors. This is also the exit() entry.
|
||||
|
||||
_exit: pha ; Save the return code on stack
|
||||
jsr donelib
|
||||
|
||||
; Copy back the zero page stuff
|
||||
; Copy back the zero-page stuff.
|
||||
|
||||
ldx #zpspace-1
|
||||
L2: lda zpsave,x
|
||||
@ -78,17 +78,17 @@ L2: lda zpsave,x
|
||||
dex
|
||||
bpl L2
|
||||
|
||||
; Store the program return code into ST
|
||||
; Store the program return code into BASIC's status variable.
|
||||
|
||||
pla
|
||||
sta ST
|
||||
|
||||
; Restore the stack pointer
|
||||
; Restore the stack pointer.
|
||||
|
||||
ldx spsave
|
||||
txs ; Restore stack pointer
|
||||
|
||||
; Back to basic
|
||||
; Back to BASIC.
|
||||
|
||||
rts
|
||||
|
||||
|
||||
@ -29,7 +29,7 @@ IRQInd = $500 ; JMP $0000 - used as indirect IRQ vector
|
||||
|
||||
Start:
|
||||
|
||||
; Save the zero page locations we need
|
||||
; Save the zero-page locations that we need.
|
||||
|
||||
sei ; No interrupts since we're banking out the ROM
|
||||
sta ENABLE_RAM
|
||||
@ -41,13 +41,13 @@ L1: lda sp,x
|
||||
sta ENABLE_ROM
|
||||
cli
|
||||
|
||||
; Switch to second charset
|
||||
; Switch to the second charset.
|
||||
|
||||
lda #14
|
||||
jsr $FFD2 ; BSOUT
|
||||
|
||||
; Save system stuff and setup the stack. The stack starts at the top of the
|
||||
; usable RAM.
|
||||
; Save some system stuff; and, set up the stack. The stack starts at the top
|
||||
; of the usable RAM.
|
||||
|
||||
tsx
|
||||
stx spsave ; save system stk ptr
|
||||
@ -57,7 +57,7 @@ L1: lda sp,x
|
||||
lda #>(__RAM_START__ + __RAM_SIZE__ + __STACKSIZE__)
|
||||
sta sp+1
|
||||
|
||||
; Setup the IRQ vector in the banked RAM and switch off the ROM
|
||||
; Set up the IRQ vector in the banked RAM; and, switch off the ROM.
|
||||
|
||||
ldx #<IRQ
|
||||
ldy #>IRQ
|
||||
@ -67,35 +67,35 @@ L1: lda sp,x
|
||||
sty $FFFF
|
||||
cli ; Allow interrupts
|
||||
|
||||
; Clear the BSS data
|
||||
; Clear the BSS data.
|
||||
|
||||
jsr zerobss
|
||||
|
||||
; Initialize irqcount, which means that from now own custom linked in IRQ
|
||||
; handlers (via condes) will be called.
|
||||
; Initialize irqcount, which means that, from now on, custom linked-in IRQ
|
||||
; handlers will be called (via condes).
|
||||
|
||||
lda #.lobyte(__INTERRUPTOR_COUNT__*2)
|
||||
sta irqcount
|
||||
|
||||
; Call module constructors
|
||||
; Call the module constructors.
|
||||
|
||||
jsr initlib
|
||||
|
||||
; Push arguments and call main()
|
||||
; Push the command-line arguments; and, call main().
|
||||
|
||||
jsr callmain
|
||||
|
||||
; Back from main (this is also the _exit entry). Run module destructors.
|
||||
; Back from main() [this is also the exit() entry]. Run the module destructors.
|
||||
|
||||
_exit: pha ; Save the return code
|
||||
jsr donelib ; Run module destructors
|
||||
|
||||
; Disable chained IRQ handlers
|
||||
; Disable the chained IRQ handlers.
|
||||
|
||||
lda #0
|
||||
sta irqcount ; Disable custom IRQ handlers
|
||||
|
||||
; Copy back the zero page stuff
|
||||
; Copy back the zero-page stuff.
|
||||
|
||||
ldx #zpspace-1
|
||||
L2: lda zpsave,x
|
||||
@ -103,28 +103,28 @@ L2: lda zpsave,x
|
||||
dex
|
||||
bpl L2
|
||||
|
||||
; Place the program return code into ST
|
||||
; Place the program return code into BASIC's status variable.
|
||||
|
||||
pla
|
||||
sta ST
|
||||
|
||||
; Restore the stack pointer
|
||||
; Restore the stack pointer.
|
||||
|
||||
ldx spsave
|
||||
txs
|
||||
|
||||
; Enable the ROM and return to BASIC
|
||||
; Enable the ROM; and, return to BASIC.
|
||||
|
||||
sta ENABLE_ROM
|
||||
rts
|
||||
|
||||
; ------------------------------------------------------------------------
|
||||
; IRQ handler. The handler in the ROM enables the kernal and jumps to
|
||||
; $CE00, where the ROM code checks for a BRK or IRQ and branches via the
|
||||
; IRQ handler. The handler in the ROM enables the Kernal, and jumps to
|
||||
; $CE00, where the ROM code checks for a BRK or IRQ, and branches via the
|
||||
; indirect vectors at $314/$316.
|
||||
; To make our stub as fast as possible, we skip the whole part of the ROM
|
||||
; handler and jump to the indirect vectors directly. We do also call our
|
||||
; own interrupt handlers if we have any, so they need not use $314.
|
||||
; handler, and jump to the indirect vectors directly. We do also call our
|
||||
; own interrupt handlers if we have any; so, they need not use $314.
|
||||
|
||||
.segment "LOWCODE"
|
||||
|
||||
@ -139,7 +139,7 @@ IRQ: cld ; Just to be sure
|
||||
and #$10 ; Test for BRK bit
|
||||
bne dobreak
|
||||
|
||||
; It's an IRQ and RAM is enabled. If we have handlers, call them. We will use
|
||||
; It's an IRQ; and, RAM is enabled. If we have handlers, call them. We will use
|
||||
; a flag here instead of loading __INTERRUPTOR_COUNT__ directly, since the
|
||||
; condes function is not reentrant. The irqcount flag will be set/reset from
|
||||
; the main code, to avoid races.
|
||||
@ -149,8 +149,8 @@ IRQ: cld ; Just to be sure
|
||||
jsr callirq_y ; Call the IRQ functions
|
||||
|
||||
; Since the ROM handler will end with an RTI, we have to fake an IRQ return
|
||||
; on stack, so we get control of the CPU after the ROM handler and can switch
|
||||
; back to RAM.
|
||||
; on the stack, so that we get control of the CPU after the ROM handler,
|
||||
; and can switch back to RAM.
|
||||
|
||||
@L1: lda #>irq_ret ; Push new return address
|
||||
pha
|
||||
@ -161,7 +161,7 @@ IRQ: cld ; Just to be sure
|
||||
pha ; Push faked X register
|
||||
pha ; Push faked Y register
|
||||
sta ENABLE_ROM ; Switch to ROM
|
||||
jmp (IRQVec) ; Jump indirect to kernal irq handler
|
||||
jmp (IRQVec) ; Jump indirect to Kernal IRQ handler
|
||||
|
||||
irq_ret:
|
||||
sta ENABLE_RAM ; Switch back to RAM
|
||||
@ -177,7 +177,7 @@ dobreak:
|
||||
beq nohandler
|
||||
jmp brk_jmp ; Jump to the handler
|
||||
|
||||
; No break handler installed, jump to ROM
|
||||
; No break handler installed, jump to ROM.
|
||||
|
||||
nohandler:
|
||||
sta ENABLE_ROM
|
||||
|
||||
@ -28,7 +28,7 @@ _sv_nmi_counter: .byte 0
|
||||
reset:
|
||||
jsr zerobss
|
||||
|
||||
; initialize data
|
||||
; Initialize data.
|
||||
jsr copydata
|
||||
|
||||
lda #>(__RAM_START__ + __RAM_SIZE__ + __STACKSIZE__)
|
||||
@ -63,12 +63,12 @@ not_dma:
|
||||
rti
|
||||
.endproc
|
||||
|
||||
; removing this segment gives only a warning
|
||||
; Removing this segment gives only a warning.
|
||||
.segment "FFF0"
|
||||
.proc reset32kcode
|
||||
lda #(6<<5)
|
||||
sta sv_bank
|
||||
; now the 32kbyte image can reside in the top of 64kbyte, 128kbyte roms
|
||||
; Now, the 32Kbyte image can reside in the top of 64Kbyte and 128Kbyte ROMs.
|
||||
jmp reset
|
||||
.endproc
|
||||
|
||||
|
||||
@ -22,7 +22,7 @@
|
||||
|
||||
Start:
|
||||
|
||||
; Save the zero page locations we need
|
||||
; Save the zero-page locations that we need.
|
||||
|
||||
ldx #zpspace-1
|
||||
L1: lda sp,x
|
||||
@ -30,16 +30,16 @@ L1: lda sp,x
|
||||
dex
|
||||
bpl L1
|
||||
|
||||
; Switch to second charset
|
||||
; Switch to the second charset.
|
||||
|
||||
lda #14
|
||||
jsr BSOUT
|
||||
|
||||
; Clear the BSS data
|
||||
; Clear the BSS data.
|
||||
|
||||
jsr zerobss
|
||||
|
||||
; Save system stuff and setup the stack
|
||||
; Save some system stuff; and, set up the stack.
|
||||
|
||||
tsx
|
||||
stx spsave ; Save the system stack ptr
|
||||
@ -49,20 +49,20 @@ L1: lda sp,x
|
||||
lda #>(__RAM_START__ + __RAM_SIZE__ + __STACKSIZE__)
|
||||
sta sp+1 ; Set argument stack ptr
|
||||
|
||||
; Call module constructors
|
||||
; Call the module constructors.
|
||||
|
||||
jsr initlib
|
||||
|
||||
; Push arguments and call main()
|
||||
; Push the command-line arguments; and, call main().
|
||||
|
||||
jsr callmain
|
||||
|
||||
; Back from main (This is also the _exit entry). Run module destructors
|
||||
; Back from main() [this is also the exit() entry]. Run the module destructors.
|
||||
|
||||
_exit: pha ; Save the return code on stack
|
||||
jsr donelib
|
||||
|
||||
; Copy back the zero page stuff
|
||||
; Copy back the zero-page stuff.
|
||||
|
||||
ldx #zpspace-1
|
||||
L2: lda zpsave,x
|
||||
@ -70,17 +70,17 @@ L2: lda zpsave,x
|
||||
dex
|
||||
bpl L2
|
||||
|
||||
; Place the program return code into ST
|
||||
; Place the program return code into BASIC's status variable.
|
||||
|
||||
pla
|
||||
sta ST
|
||||
|
||||
; Restore the stack pointer
|
||||
; Restore the stack pointer.
|
||||
|
||||
ldx spsave
|
||||
txs
|
||||
|
||||
; Back to basic
|
||||
; Back to BASIC.
|
||||
|
||||
rts
|
||||
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user