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fix Z80 offset

This commit is contained in:
Peter Ferrie 2022-10-10 13:58:07 -07:00
parent 87cb39221b
commit bc4b495632
1 changed files with 5 additions and 4 deletions
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9
src/hw.mockingboard.a
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@ -27,7 +27,7 @@
; A/Y clobbered
;------------------------------------------------------------------------------
MAGIC_Z80_LOCATION=$FFC
MAGIC_Z80_LOCATION=$FFD
GetMockingboardStuff
+ST16 @callback+1
@ -36,10 +36,11 @@ GetMockingboardStuff
; https://github.com/a2-4am/4cade/issues/483
; the Mockingboard init can accidentally enable the Softcard Z80
; and can crash the machine
; solved by loading a small Z80 routine at $0FFC (FFFCh in the Z80 space):
; $32 $00 $E4 $C3 FC FF which is
; solved by loading a small Z80 routine at $0FFD (FFFDh in the Z80 space):
; $32 $00 $E4 $C3 FD FF which is
; NOP
; LD (E400h),A ; card is at $E400 due to memory translation
; JP FFFCh
; JP FFFDh
; returns the system to 6502 mode and leaves it in the same state as the Z80 after RESET:
; ready to execute the instruction at 0000h (from the Z80 perspective)
ldx #5