pt3_player: add iic support

This commit is contained in:
Vince Weaver 2019-06-07 16:52:31 -04:00
parent 3bdc522ec7
commit 0efd367bfa
3 changed files with 45 additions and 9 deletions

View File

@ -13,7 +13,8 @@
TIME_OFFSET EQU 13
interrupt_handler:
; pha ; save A ; 3
php
pha ; save A ; 3
; A is saved in $45 by firmware
txa
pha ; save X
@ -292,8 +293,13 @@ exit_interrupt:
tay ; restore Y
pla
tax ; restore X
pla ; restore a ; 4
; this is needed on II+/IIe not not IIc
interrupt_smc:
lda $45 ; restore A
; pla ; restore a ; 4
plp
rti ; return from interrupt ; 6

View File

@ -27,18 +27,47 @@ pt3_setup:
jsr clear_screens
;=======================
; Check for Apple II/II+
;=======================
;===============================
; Check for Apple II/II+/IIe/IIc
;===============================
; this is used to see if we have lowecase support
lda $FBB3 ; IIe and newer is $06
cmp #6
beq apple_iie
beq apple_iie_or_newer
lda #1 ; set if older than a IIe
sta apple_ii
apple_iie:
jmp done_apple_detect
apple_iie_or_newer:
lda $FBC0 ; 0 on a IIc
bne done_apple_detect
apple_iic:
; activate IIc mockingboard?
; this might only be necessary to allow detection
; I get the impression the Mockingboard 4c activates
; when you access any of the 6522 ports in Slot 4
lda #$ff
sta $C403
sta $C404
; bypass the firmware interrupt handler
; should we do this on IIe too? probably faster
sei ; disable interrupts
lda $c08b ; disable ROM (enable language card)
lda $c08b
lda #<interrupt_handler
sta $fffe
lda #>interrupt_handler
sta $ffff
lda #$EA ; nop out the "lda $45" in the irq hand
sta interrupt_smc
sta interrupt_smc+1
done_apple_detect:
;===============
; Init disk code

View File

@ -73,8 +73,9 @@ rts_init:
sta mlsmc04+1
sta mlsmc05+1
jsr $fe93 ; clear COUT
jsr $fe89 ; clear KEYIN
; Are these needed? they break on iic as we have ROM turned off
; jsr $fe93 ; clear COUT
; jsr $fe89 ; clear KEYIN
;========================
; Create nibble table