mirror of
https://github.com/deater/dos33fsprogs.git
synced 2024-11-17 14:12:58 +00:00
257 lines
6.4 KiB
ArmAsm
257 lines
6.4 KiB
ArmAsm
; Mockingboad programming:
|
|
; + Has two 6522 I/O chips connected to two AY-3-8910 chips
|
|
; + Optionally has some speech chips controlled via the outport on the AY
|
|
; + Often in slot 4
|
|
; TODO: how to auto-detect?
|
|
; References used:
|
|
; http://macgui.com/usenet/?group=2&id=8366
|
|
; 6522 Data Sheet
|
|
; AY-3-8910 Data Sheet
|
|
|
|
;========================
|
|
; Mockingboard card
|
|
; Essentially two 6522s hooked to the Apple II bus
|
|
; Connected to AY-3-8910 chips
|
|
; PA0-PA7 on 6522 connected to DA0-DA7 on AY
|
|
; PB0 on 6522 connected to BC1
|
|
; PB1 on 6522 connected to BDIR
|
|
; PB2 on 6522 connected to RESET
|
|
|
|
|
|
; left speaker
|
|
MOCK_6522_ORB1 = $C400 ; 6522 #1 port b data
|
|
MOCK_6522_ORA1 = $C401 ; 6522 #1 port a data
|
|
MOCK_6522_DDRB1 = $C402 ; 6522 #1 data direction port B
|
|
MOCK_6522_DDRA1 = $C403 ; 6522 #1 data direction port A
|
|
MOCK_6522_T1CL = $C404 ; 6522 #1 t1 low order latches
|
|
MOCK_6522_T1CH = $C405 ; 6522 #1 t1 high order counter
|
|
MOCK_6522_T1LL = $C406 ; 6522 #1 t1 low order latches
|
|
MOCK_6522_T1LH = $C407 ; 6522 #1 t1 high order latches
|
|
MOCK_6522_T2CL = $C408 ; 6522 #1 t2 low order latches
|
|
MOCK_6522_T2CH = $C409 ; 6522 #1 t2 high order counters
|
|
MOCK_6522_SR = $C40A ; 6522 #1 shift register
|
|
MOCK_6522_ACR = $C40B ; 6522 #1 auxilliary control register
|
|
MOCK_6522_PCR = $C40C ; 6522 #1 peripheral control register
|
|
MOCK_6522_IFR = $C40D ; 6522 #1 interrupt flag register
|
|
MOCK_6522_IER = $C40E ; 6522 #1 interrupt enable register
|
|
MOCK_6522_ORANH = $C40F ; 6522 #1 port a data no handshake
|
|
|
|
|
|
; right speaker
|
|
MOCK_6522_ORB2 = $C480 ; 6522 #2 port b data
|
|
MOCK_6522_ORA2 = $C481 ; 6522 #2 port a data
|
|
MOCK_6522_DDRB2 = $C482 ; 6522 #2 data direction port B
|
|
MOCK_6522_DDRA2 = $C483 ; 6522 #2 data direction port A
|
|
|
|
; AY-3-8910 commands on port B
|
|
; RESET BDIR BC1
|
|
MOCK_AY_RESET = $0 ; 0 0 0
|
|
MOCK_AY_INACTIVE = $4 ; 1 0 0
|
|
MOCK_AY_READ = $5 ; 1 0 1
|
|
MOCK_AY_WRITE = $6 ; 1 1 0
|
|
MOCK_AY_LATCH_ADDR = $7 ; 1 1 1
|
|
|
|
|
|
;========================
|
|
;========================
|
|
; Mockingboard Init
|
|
;========================
|
|
;========================
|
|
|
|
mockingboard_init:
|
|
|
|
;=========================
|
|
; Initialize the 6522s
|
|
; set the data direction for all pins of PortA/PortB to be output
|
|
|
|
|
|
lda #$ff ; all output (1)
|
|
|
|
sta MOCK_6522_DDRB1 ; set for 6522 #1
|
|
sta MOCK_6522_DDRA1
|
|
|
|
sta MOCK_6522_DDRB2 ; set for 6522 #2
|
|
sta MOCK_6522_DDRA2
|
|
|
|
|
|
mockingboard_setup_interrupt:
|
|
|
|
;=========================
|
|
; Setup Interrupt Handler
|
|
;=========================
|
|
|
|
; NOTE: we don't support IIc as it's a hack
|
|
; traditionally Mockingboard on IIc was rare
|
|
|
|
;========================
|
|
; set up interrupt
|
|
; Vector address goes to 0x3fe/0x3ff
|
|
|
|
lda #<interrupt_handler
|
|
sta $03fe
|
|
lda #>interrupt_handler
|
|
sta $03ff
|
|
|
|
;============================
|
|
; Enable 50Hz clock on 6522
|
|
;============================
|
|
|
|
|
|
; Note, on Apple II the clock isn't 1MHz but is actually closer to
|
|
; roughly 1.023MHz, and every 65th clock is stretched (it's complicated)
|
|
|
|
; c7ce / 1.023e6 = .050s, 20Hz
|
|
; 9c40 / 1.023e6 = .040s, 25Hz
|
|
; 8534 / 1.023e6 = .033s, 30Hz
|
|
; 4fe7 / 1.023e6 = .020s, 50Hz
|
|
; 411a / 1.023e6 = .016s, 60Hz
|
|
|
|
; French Touch uses
|
|
; 4e20 / 1.000e6 = .020s, 50Hz, which assumes 1MHz clock freq
|
|
|
|
sei ; disable interrupts just in case
|
|
|
|
lda #$40 ; Continuous interrupts, don't touch PB7
|
|
sta MOCK_6522_ACR ; ACR register
|
|
|
|
lda #$7F ; clear all interrupt flags
|
|
sta MOCK_6522_IER ; IER register (interrupt enable)
|
|
|
|
lda #$C0
|
|
sta MOCK_6522_IFR ; IFR: 1100, enable interrupt on timer one oflow
|
|
sta MOCK_6522_IER ; IER: 1100, enable timer one interrupt
|
|
|
|
lda #$CE
|
|
; lda #$40
|
|
; lda #$34
|
|
; lda #$E7
|
|
sta MOCK_6522_T1CL ; write into low-order latch
|
|
|
|
lda #$C7
|
|
; lda #$9C
|
|
; lda #$85
|
|
; lda #$4f
|
|
sta MOCK_6522_T1CH ; write into high-order latch,
|
|
; load both values into counter
|
|
; clear interrupt and start counting
|
|
|
|
|
|
|
|
;===================================
|
|
;===================================
|
|
; Reset Both AY-3-8910s
|
|
;===================================
|
|
;===================================
|
|
|
|
;===========================
|
|
; Reset Right/Left AY-3-8910
|
|
;===========================
|
|
lda #MOCK_AY_RESET
|
|
sta MOCK_6522_ORB1
|
|
sta MOCK_6522_ORB2
|
|
lda #MOCK_AY_INACTIVE
|
|
sta MOCK_6522_ORB1
|
|
sta MOCK_6522_ORB2
|
|
|
|
init_registers:
|
|
|
|
; init song data
|
|
|
|
lda #0
|
|
sta SONG_OFFSET
|
|
sta SONG_COUNTDOWN
|
|
|
|
; read 14 bytes from beginning of song to init
|
|
|
|
ldx #13
|
|
init_loop:
|
|
init_smc:
|
|
txa
|
|
tay
|
|
lda (SONG_L),Y
|
|
jsr ay3_write_reg ; trashes Y
|
|
dex
|
|
bne init_loop
|
|
|
|
; update SONG_L to point past the init
|
|
lda SONG_L
|
|
clc
|
|
adc #14
|
|
sta SONG_L
|
|
bcc no_oflo
|
|
inc SONG_H
|
|
no_oflo:
|
|
|
|
; create Frequency Table
|
|
ldx #11
|
|
make_freq_loop:
|
|
sec
|
|
lda frequency_lookup_low,X
|
|
ror
|
|
sta frequency_lookup_low+16,X
|
|
lsr
|
|
sta frequency_lookup_low+32,X
|
|
lsr
|
|
sta frequency_lookup_low+48,X
|
|
|
|
dex
|
|
bpl make_freq_loop
|
|
|
|
inx
|
|
stx frequency_lookup_low+28
|
|
|
|
rts
|
|
|
|
|
|
;=====================
|
|
;=====================
|
|
;=====================
|
|
; ay3 write reg
|
|
;=====================
|
|
;=====================
|
|
;=====================
|
|
; writes to both chips (so same output to both Right/Left)
|
|
; address in X (preserved)
|
|
; value in A
|
|
|
|
; NOTE: it looks like you could interleave things to save bytes
|
|
; but technically this violates the AY-3-8910 spec sheet on
|
|
; finishing accesses in less than 10us (10 cycles)
|
|
|
|
ay3_write_reg:
|
|
pha
|
|
lda #MOCK_AY_LATCH_ADDR ; latch_address for PB1 ; 2
|
|
ldy #MOCK_AY_INACTIVE ; go inactive ; 2
|
|
|
|
stx MOCK_6522_ORA1 ; put address on PA1 ; 4
|
|
sta MOCK_6522_ORB1 ; latch_address on PB1 ; 4
|
|
sty MOCK_6522_ORB1 ; 4
|
|
|
|
stx MOCK_6522_ORA2 ; put address on PA2 ; 4
|
|
sta MOCK_6522_ORB2 ; latch_address on PB2 ; 4
|
|
sty MOCK_6522_ORB2 ; 4
|
|
pla
|
|
|
|
; value
|
|
sta MOCK_6522_ORA1 ; put value on PA1 ; 4
|
|
sta MOCK_6522_ORA2 ; put value on PA2 ; 4
|
|
lda #MOCK_AY_WRITE ; ; 2
|
|
|
|
sta MOCK_6522_ORB1 ; write on PB1 ; 4
|
|
sty MOCK_6522_ORB1 ; 4
|
|
|
|
sta MOCK_6522_ORB2 ; write on PB2 ; 4
|
|
sty MOCK_6522_ORB2 ; 4
|
|
|
|
rts
|
|
|
|
|
|
; starts at C4
|
|
frequency_lookup_low:
|
|
.byte $E8,$CD,$B3,$9B,$83,$6E,$59,$46,$33,$22,$12,$02
|
|
|
|
;$1E8,$1CD,$1B3,$19B,$183,$16E,$159,$146,$133,$122,$112,$102,
|
|
;.byte $F4,$E6,$D9,$CD,$C1,$B7,$AC,$A3,$99,$91,$89,$81,$00,$00,$00,$00
|
|
;.byte $7A,$73,$6C,$66,$60,$5B,$56,$51,$4C,$48,$44,$40,$00,$00,$00,$00
|
|
;.byte $3D,$39,$36,$33,$30,$2D,$2B,$28,$26,$24,$22,$20,$00,$00,$00,$00
|