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186 lines
3.7 KiB

PORTB = $6000
PORTA = $6001
DDRB = $6002
DDRA = $6003
E = %10000000
RW = %01000000
RS = %00100000
.org $8000
reset:
lda #%11111111 ; Set all pins on port B to output
sta DDRB
lda #%11100000 ; Set top 3 pins on port A to output
sta DDRA
lda #%00111000 ; Set 8-bit mode; 2-line display; 5x8 font
sta PORTB
lda #0 ; Clear RS/RW/E bits
sta PORTA
lda #E ; Set E bit to send instruction
sta PORTA
lda #0 ; Clear RS/RW/E bits
sta PORTA
lda #%00001110 ; Display on; cursor on; blink off
sta PORTB
lda #0 ; Clear RS/RW/E bits
sta PORTA
lda #E ; Set E bit to send instruction
sta PORTA
lda #0 ; Clear RS/RW/E bits
sta PORTA
lda #%00000110 ; Increment and shift cursor; don't shift display
sta PORTB
lda #0 ; Clear RS/RW/E bits
sta PORTA
lda #E ; Set E bit to send instruction
sta PORTA
lda #0 ; Clear RS/RW/E bits
sta PORTA
lda #"H"
sta PORTB
lda #RS ; Set RS; Clear RW/E bits
sta PORTA
lda #(RS | E) ; Set E bit to send instruction
sta PORTA
lda #RS ; Clear E bits
sta PORTA
lda #"e"
sta PORTB
lda #RS ; Set RS; Clear RW/E bits
sta PORTA
lda #(RS | E) ; Set E bit to send instruction
sta PORTA
lda #RS ; Clear E bits
sta PORTA
lda #"l"
sta PORTB
lda #RS ; Set RS; Clear RW/E bits
sta PORTA
lda #(RS | E) ; Set E bit to send instruction
sta PORTA
lda #RS ; Clear E bits
sta PORTA
lda #"l"
sta PORTB
lda #RS ; Set RS; Clear RW/E bits
sta PORTA
lda #(RS | E) ; Set E bit to send instruction
sta PORTA
lda #RS ; Clear E bits
sta PORTA
lda #"o"
sta PORTB
lda #RS ; Set RS; Clear RW/E bits
sta PORTA
lda #(RS | E) ; Set E bit to send instruction
sta PORTA
lda #RS ; Clear E bits
sta PORTA
lda #","
sta PORTB
lda #RS ; Set RS; Clear RW/E bits
sta PORTA
lda #(RS | E) ; Set E bit to send instruction
sta PORTA
lda #RS ; Clear E bits
sta PORTA
lda #" "
sta PORTB
lda #RS ; Set RS; Clear RW/E bits
sta PORTA
lda #(RS | E) ; Set E bit to send instruction
sta PORTA
lda #RS ; Clear E bits
sta PORTA
lda #"k"
sta PORTB
lda #RS ; Set RS; Clear RW/E bits
sta PORTA
lda #(RS | E) ; Set E bit to send instruction
sta PORTA
lda #RS ; Clear E bits
sta PORTA
lda #"i"
sta PORTB
lda #RS ; Set RS; Clear RW/E bits
sta PORTA
lda #(RS | E) ; Set E bit to send instruction
sta PORTA
lda #RS ; Clear E bits
sta PORTA
lda #"d"
sta PORTB
lda #RS ; Set RS; Clear RW/E bits
sta PORTA
lda #(RS | E) ; Set E bit to send instruction
sta PORTA
lda #RS ; Clear E bits
sta PORTA
lda #"d"
sta PORTB
lda #RS ; Set RS; Clear RW/E bits
sta PORTA
lda #(RS | E) ; Set E bit to send instruction
sta PORTA
lda #RS ; Clear E bits
sta PORTA
lda #"i"
sta PORTB
lda #RS ; Set RS; Clear RW/E bits
sta PORTA
lda #(RS | E) ; Set E bit to send instruction
sta PORTA
lda #RS ; Clear E bits
sta PORTA
lda #"e"
sta PORTB
lda #RS ; Set RS; Clear RW/E bits
sta PORTA
lda #(RS | E) ; Set E bit to send instruction
sta PORTA
lda #RS ; Clear E bits
sta PORTA
lda #"s"
sta PORTB
lda #RS ; Set RS; Clear RW/E bits
sta PORTA
lda #(RS | E) ; Set E bit to send instruction
sta PORTA
lda #RS ; Clear E bits
sta PORTA
lda #"!"
sta PORTB
lda #RS ; Set RS; Clear RW/E bits
sta PORTA
lda #(RS | E) ; Set E bit to send instruction
sta PORTA
lda #RS ; Clear E bits
sta PORTA
loop:
jmp loop
.org $fffc
.word reset
.word $0000