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cc65/libsrc/osic1p/bootstrap.s

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ArmAsm
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Added a second OSI C1P program file format. Unlike the first format, the new format is already loadable; it doesn't need to be converted.
2015-03-07 21:37:58 +00:00
;
Described how to change the boot loader's actions.
2015-03-08 14:06:00 +00:00
; 2015-03-08, Greg King
Added a second OSI C1P program file format. Unlike the first format, the new format is already loadable; it doesn't need to be converted.
2015-03-07 21:37:58 +00:00
;
; When you want to create a program with the alternate file format,
; add "-u __BOOT__" to the cl65/ld65 command line. Then, the linker
; will import this symbol name; and, link this module at the front
; of your program file.
Renamed RAM to MAIN for all disk based targets. The name RAM doesn't make much sense in general for a memeory area because i.e. the zero page is for sure RAM but is not part of the memory area named RAM. For disk based targets it makes sense to put the disk file more into focus and here MAIN means the main part of the file - in contrast to some header. Only for ROM based targets the name RAM is kept as it makes sense to focus on the difference between RAM and ROM.
2016-03-07 00:28:55 +00:00
.export __BOOT__ : abs = 1
.import __MAIN_START__, __MAIN_SIZE__, __BSS_RUN__
Added a second OSI C1P program file format. Unlike the first format, the new format is already loadable; it doesn't need to be converted.
2015-03-07 21:37:58 +00:00
; ------------------------------------------------------------------------
Renamed RAM to MAIN for all disk based targets. The name RAM doesn't make much sense in general for a memeory area because i.e. the zero page is for sure RAM but is not part of the memory area named RAM. For disk based targets it makes sense to put the disk file more into focus and here MAIN means the main part of the file - in contrast to some header. Only for ROM based targets the name RAM is kept as it makes sense to focus on the difference between RAM and ROM.
2016-03-07 00:28:55 +00:00
load_addr := __MAIN_START__
load_size = __BSS_RUN__ - __MAIN_START__
ram_top := __MAIN_START__ + __MAIN_SIZE__
Added a second OSI C1P program file format. Unlike the first format, the new format is already loadable; it doesn't need to be converted.
2015-03-07 21:37:58 +00:00
.segment "BOOT"
Described how to change the boot loader's actions.
2015-03-08 14:06:00 +00:00
; If you want to change how this bootstrap loader works, then:
; 1. edit this assembly source code,
; 2. define the constant ASM (uncomment the line below),
; 3. assemble this file (and, make a listing of that assembly),
; 4. copy the listing's hex codes into the .byte lines below (notice that most
; of the strings are followed by CR; it's required by the OS65V monitor)
; (be sure to match the listing's lines against the .byte lines),
; 5. undefine ASM (recomment the line),
; 6. assemble this file, again,
; 7. and, add the object file to "osic1p.lib".
;ASM = 1
Added a second OSI C1P program file format. Unlike the first format, the new format is already loadable; it doesn't need to be converted.
2015-03-07 21:37:58 +00:00
.ifdef ASM
.include "osic1p.inc"
.macpack generic
load := $08 ; private variables
count := $0A
GETCHAR := $FFBF ; gets one character from ACIA
FIRSTVISC = $85 ; Offset of first visible character in video RAM
LINEDIST = $20 ; Offset in video RAM between two lines
Improved fix with suggestions by Greg King.
2015-03-14 23:40:42 +00:00
ldy #<$0000
Added a second OSI C1P program file format. Unlike the first format, the new format is already loadable; it doesn't need to be converted.
2015-03-07 21:37:58 +00:00
lda #<load_addr
ldx #>load_addr
Improved fix with suggestions by Greg King.
2015-03-14 23:40:42 +00:00
sta load
Added a second OSI C1P program file format. Unlike the first format, the new format is already loadable; it doesn't need to be converted.
2015-03-07 21:37:58 +00:00
stx load+1
Use more compact loops.
2020-11-01 21:59:07 +00:00
Fold constant calculation.
2020-11-03 10:52:58 +00:00
ldx #(<load_size) + 1
Use more compact loops.
2020-11-01 21:59:07 +00:00
stx count
Fold constant calculation.
2020-11-03 10:52:58 +00:00
ldx #(>load_size) + 1
Use more compact loops.
2020-11-01 21:59:07 +00:00
stx count+1 ; save size with each byte incremented separately
Remove stale comment.
2020-11-03 10:53:56 +00:00
L1: dec count
Added a second OSI C1P program file format. Unlike the first format, the new format is already loadable; it doesn't need to be converted.
2015-03-07 21:37:58 +00:00
bnz L2
Use more compact loops.
2020-11-01 21:59:07 +00:00
dec count+1
Added a second OSI C1P program file format. Unlike the first format, the new format is already loadable; it doesn't need to be converted.
2015-03-07 21:37:58 +00:00
bze L3
L2: jsr GETCHAR ; (doesn't change .Y)
sta (load),y
; Show that the file is being loaded by rotating an arrow on the screen.
;
tya
lsr a
lsr a
and #8 - 1
ora #$10 ; eight arrow characters
sta SCRNBASE + FIRSTVISC + 2 * LINEDIST + 11
iny
bnz L1
inc load+1
bnz L1 ; branch always
L3: jmp load_addr
.else
.mac hex1 h
.lobytes ((h) & $0F) + (((h) & $0F) > 9) * 7 + '0'
.endmac
.mac hex2 h
hex1 (h) >> 4
hex1 (h) >> 0
.endmac
.mac hex4 h
hex2 >(h)
hex2 <(h)
.endmac
CR = $0D
.byte CR, CR
.byte "." ; set an address
hex4 ram_top ; put loader where stack will sit
.byte "/" ; write bytes into RAM
; ASCII-coded hexadecimal translation of the above assembly code.
; It was copied from the assembler listing.
Improved fix with suggestions by Greg King.
2015-03-14 23:40:42 +00:00
.byte "A0", CR, "00", CR
Added a second OSI C1P program file format. Unlike the first format, the new format is already loadable; it doesn't need to be converted.
2015-03-07 21:37:58 +00:00
.byte "A9", CR
hex2 <load_addr
.byte CR, "A2", CR
hex2 >load_addr
Improved fix with suggestions by Greg King.
2015-03-14 23:40:42 +00:00
.byte CR, "85", CR, "08", CR
Added a second OSI C1P program file format. Unlike the first format, the new format is already loadable; it doesn't need to be converted.
2015-03-07 21:37:58 +00:00
.byte "86", CR, "09", CR
.byte "A9", CR
hex2 <load_size
.byte CR, "49", CR, "FF", CR
.byte "85", CR, "0A", CR
.byte "A9", CR
hex2 >load_size
.byte CR, "49", CR, "FF", CR
.byte "85", CR, "0B", CR
.byte "E6", CR, "0A", CR
.byte "D0", CR, "04", CR
.byte "E6", CR, "0B", CR
.byte "F0", CR, "16", CR
.byte "20", CR, "BF", CR, "FF", CR
.byte "91", CR, "08", CR
.byte "98", CR
.byte "4A", CR
.byte "4A", CR
.byte "29", CR, "07", CR
.byte "09", CR, "10", CR
.byte "8D", CR, "D0", CR, "D0", CR
.byte "C8", CR
.byte "D0", CR, "E6", CR
.byte "E6", CR, "09", CR
.byte "D0", CR, "E2", CR
.byte "4C", CR
hex2 <load_addr
.byte CR
hex2 >load_addr
.byte CR, "."
hex4 ram_top
.byte "G" ; go to address
.endif
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