41 lines
767 B
ArmAsm
41 lines
767 B
ArmAsm
; Code from TotalReplay by 4am and qkumba
|
|
|
|
;------------------------------------------------------------------------------
|
|
; Has64K
|
|
; Checks whether computer has functioning language card (64K)
|
|
;
|
|
; in: none
|
|
; out: C clear if 64K detected
|
|
; C set if 64K not detected
|
|
; all other flags and registers clobbered
|
|
; ROM in memory (not LC RAM bank)
|
|
;------------------------------------------------------------------------------
|
|
|
|
detect_language_card:
|
|
|
|
; enable language card
|
|
; READ_RAM1_WRITE_RAM1
|
|
|
|
bit $C08B
|
|
bit $C08B
|
|
|
|
lda #$AA ; test #1 for $D0 page
|
|
sta $D000
|
|
eor $D000
|
|
bne no_lc
|
|
lsr $D000 ; test #2 for $D0 page
|
|
lda #$55
|
|
eor $D000
|
|
bne no_lc
|
|
clc
|
|
bcc done_detect
|
|
|
|
no_lc:
|
|
sec
|
|
|
|
done_detect:
|
|
; READ_ROM_NO_WRITE
|
|
bit $C08A
|
|
|
|
rts
|