more Z80 optimizations

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FeralChild64 authored and FeralChild64 committed 2021-01-26 00:03:07 +01:00
1 parent c9572d48df
commit d3b05ca2d6
17 files changed
+108 -162

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@@ -10,53 +10,23 @@ z80_table_gen:
!byte 0
;
; Generating: z80_atable_mi_bank0, z80_atable_hi_bank0
; Generating: z80_atable_bank0
; Dependencies: NONE
; Destroys: NONE
;
ldx #$00
@loop_atable_bank0:
cpx #$C0
bcs @addr_common
; Memory area $0000-$BFFF - maps somewhere to $0xxxx range - 48KB total
lda #$00
sta z80_atable_hi_bank0, x
lda #$04 ; $0000-$DFFF maps to $40000-$4DFFF (bank 0 RAM)
cpx #$E0
bcc @loop_atable_bank0_gotit
inc ; $E000-$FFFF maps to $5E000-$5FFFF (common RAM)
txa
cmp #$60
bcc @addr_lo
@loop_atable_bank0_gotit:
@addr_hi:
; Memory area $6000-$BFFF - maps to $0C000 - $0FFFF - 24 KB
clc
adc #$40
@addr_lo:
; Memory area $0000-$5FFF - maps to $02000 - $07FFF - 24 KB
adc #$20
sta z80_atable_mi_bank0, x
bra @loop_atable_next
@addr_common:
; Memory area $C000-$FFFF - maps to $5C000-$5FFFF - 16KB
lda #$05
sta z80_atable_hi_bank0, x
txa
sta z80_atable_mi_bank0, x
@loop_atable_next:
sta z80_atable_bank0, x
inx
bne @loop_atable_bank0