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More banking fixes

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git-svn-id: svn://svn.cc65.org/cc65/trunk@1090 b7a2c559-68d2-44c3-8de9-860c34a00d81
This commit is contained in:
cuz 2001-10-26 13:48:49 +00:00
parent b6476b82c6
commit b9b144cf52
1 changed files with 24 additions and 17 deletions
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41
libsrc/c128/crt0.s
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@ -70,28 +70,32 @@ Head: .word @Next
; ------------------------------------------------------------------------
; Actual code
ldx #zpspace-1
L1: lda sp,x
sta zpsave,x ; save the zero page locations we need
dex
bpl L1
; Close open files
jsr CLRCH
; Switch to second charset
; Switch to the second charset
lda #14
jsr BSOUT
; Get the current MMU setting and save it. Set new memory config.
; Before doing anything else, we have to setup our banking configuration.
; Otherwise just the lowest 16K are actually RAM. Writing through the ROM
; to the underlying RAM works, but it is bad style.
lda MMU_CR ; Get current memory configuration...
pha ; ...and save it for later
lda #CC65_MMU_CFG ; Bank0 with kernal ROM
sta MMU_CR
; Save the zero page locations we need
ldx #zpspace-1
L1: lda sp,x
sta zpsave,x
dex
bpl L1
; Clear the BSS data
jsr zerobss
@ -102,7 +106,7 @@ L1: lda sp,x
sta mmusave
tsx
stx spsave ; save system stk ptr
stx spsave ; Save the system stack pointer
lda #<(__RAM_START__ + __RAM_SIZE__)
sta sp
@ -159,12 +163,10 @@ NoIRQ2: jsr donelib
jsr doneconio
; Reset stack and the MMU
; Reset the stack
ldx spsave
txs
lda mmusave
sta MMU_CR
; Copy back the zero page stuff
@ -174,7 +176,12 @@ L2: lda zpsave,x
dex
bpl L2
; Done
; Reset the memory configuration
lda mmusave
sta MMU_CR
; Done, restore kernal vectors in an attempt to cleanup
jmp RESTOR
@ -192,10 +199,10 @@ L2: lda zpsave,x
; they have to go here.
IRQStub:
cld ; Just to be sure
lda MMU_CR ; Get old register value
pha ; And save on stack
lda #CC65_MMU_CFG ; Bank 0 with kernal ROM
cld ; Just to be sure
lda MMU_CR ; Get old register value
pha ; And save on stack
lda #CC65_MMU_CFG ; Bank 0 with kernal ROM
sta MMU_CR
ldy #<(__IRQFUNC_COUNT__*2)
lda #<__IRQFUNC_TABLE__