mirror of
https://github.com/jonthomasson/retro1.git
synced 2024-07-04 01:29:33 +00:00
292 lines
7.4 KiB
Plaintext
292 lines
7.4 KiB
Plaintext
.setcpu "65c02"
|
|
.include "macros.inc65"
|
|
|
|
.include "io.inc65"
|
|
|
|
.segment "VECTORS"
|
|
|
|
.word nmi
|
|
.word reset
|
|
.word irq
|
|
|
|
.code
|
|
|
|
reset: jmp main
|
|
|
|
nmi: rti
|
|
|
|
irq: rti
|
|
|
|
main:
|
|
|
|
jmp lcd_init2
|
|
|
|
|
|
|
|
|
|
loop:
|
|
|
|
jmp loop
|
|
lcd_init2:
|
|
lda #$ff
|
|
sta VIA2_ORA
|
|
sta VIA2_DDRA
|
|
ldx #50
|
|
jsr delay_ms
|
|
|
|
;set register select bit to 0 for command/control
|
|
|
|
;start init sequence
|
|
lda #$03
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
lda #$03
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
lda #$03
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
lda #$02
|
|
jsr strobe_enable
|
|
ldx #3
|
|
jsr delay_ms
|
|
|
|
;now in 4 bit mode
|
|
|
|
;function set
|
|
lda #$02 ;set data length to 4 bits
|
|
jsr strobe_enable
|
|
|
|
|
|
;no delay needed here
|
|
|
|
|
|
lda #$08 ;2 lines 5x8 pixels
|
|
jsr strobe_enable
|
|
ldx #3
|
|
jsr delay_ms
|
|
|
|
lda #$00 ;turn display off
|
|
jsr strobe_enable
|
|
lda #$08
|
|
jsr strobe_enable
|
|
ldx #3
|
|
jsr delay_ms
|
|
|
|
lda #$00 ;clear display
|
|
jsr strobe_enable
|
|
lda #$01
|
|
jsr strobe_enable
|
|
ldx #3
|
|
jsr delay_ms
|
|
|
|
lda #$00 ;entry mode set
|
|
jsr strobe_enable
|
|
lda #$06
|
|
jsr strobe_enable
|
|
ldx #3
|
|
jsr delay_ms
|
|
;end of initialization
|
|
|
|
lda #$00 ;turn display on
|
|
jsr strobe_enable
|
|
lda #$0f ;display on, cursor on, blink on
|
|
jsr strobe_enable
|
|
ldx #3
|
|
jsr delay_ms
|
|
|
|
lda #$00 ;CURSOR HOME
|
|
jsr strobe_enable
|
|
lda #$02 ;cursor home
|
|
jsr strobe_enable
|
|
ldx #3
|
|
jsr delay_ms
|
|
|
|
jmp write_hello_world
|
|
|
|
write_hello_world:
|
|
;send H
|
|
lda #$14
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
lda #$18
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
;send E
|
|
lda #$14
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
lda #$15
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
;add in extra strobe for reading 8 status bits
|
|
lda #00
|
|
jsr strobe_enable
|
|
lda #00
|
|
jsr strobe_enable
|
|
|
|
;send L
|
|
lda #$14
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
lda #$1C
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
;send L
|
|
lda #$14
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
lda #$1C
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
;send O
|
|
lda #$14
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
lda #$1F
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
;send space
|
|
lda #$12
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
lda #$10
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
;send W
|
|
lda #$15
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
lda #$17
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
;send O
|
|
lda #$14
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
lda #$1F
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
;send R
|
|
lda #$15
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
lda #$12
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
;send L
|
|
lda #$14
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
lda #$1C
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
;send D
|
|
lda #$14
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
lda #$14
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
;send !
|
|
lda #$12
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
lda #$11
|
|
jsr strobe_enable
|
|
ldx #5
|
|
jsr delay_ms
|
|
|
|
jmp loop
|
|
|
|
strobe_enable:
|
|
ora #$20 ;add enable bit
|
|
sta VIA2_ORA ;send value out to via
|
|
ldx #10
|
|
jsr delay_ms
|
|
and #$DF ;mask to take out enable
|
|
sta VIA2_ORA ;take out enable bit and send to via
|
|
|
|
rts
|
|
|
|
; Delay the number of miliseconds specified by X
|
|
; This is hardcoded for a 1 MHz system clock
|
|
delay_ms: pha ; 3
|
|
txa ; 2
|
|
pha ; 3
|
|
tya ; 2
|
|
pha ; 3
|
|
|
|
ldy $00 ; 3 (dummy operation)
|
|
ldy #190 ; 2
|
|
@loop1: dey ; 190 * 2
|
|
bne @loop1 ; 190 * 3 - 1
|
|
|
|
@loop2: dex ; 2
|
|
beq @return ; (x - 1) * 2 + 3
|
|
|
|
nop ; 2
|
|
ldy #198 ; 2
|
|
@loop3: dey ; 198 * 2
|
|
bne @loop3 ; 198 * 3 - 1
|
|
|
|
jmp @loop2 ; 3
|
|
|
|
@return: pla ; 4
|
|
tay ; 2
|
|
pla ; 4
|
|
tax ; 2
|
|
pla ; 4
|
|
rts ; 6 (+ 6 for JSR) |