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Back working on communication

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This commit is contained in:
Daniele Verducci su MatissePenguin
2021-01-27 08:58:04 +01:00
parent 467197fd23
commit 5bea35365d
3 changed files with 19 additions and 14 deletions
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22
pat80-io-devices/composite-pal-adapter/software/avr-assembly/communication.asm
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@@ -18,16 +18,20 @@
comm_init:
call cursor_pos_home ; Set cursor to 0,0
comm_wait_byte:
in A, DATA_PORT_IN ; read PORTB
in HIGH_ACCUM, DATA_PORT_IN ; read PORTB
; Check continuously CLK until a LOW is found
sbic PORTD, CLK_PIN
jmp comm_wait_byte
; CLK triggered: Copy PORTB to the next framebuffer byte
st Y+, A
; if reached the last framebuffer byte, exit cycle
cpi r31, 0b00111110
brne comm_wait_byte ; if not 0, repeat h_picture_loop
cpi r30, 0b11000000
brne comm_wait_byte ; if not 0, repeat h_picture_loop
jmp comm_init ; filled all memory: reset framebuffer position
; CLK triggered: Draw char
call draw_char
jmp comm_wait_byte
; ; CLK triggered: Copy PORTB to the next framebuffer byte
; st Y+, A
; ; if reached the last framebuffer byte, exit cycle
; cpi r31, 0b00111110
; brne comm_wait_byte ; if not 0, repeat h_picture_loop
; cpi r30, 0b11000000
; brne comm_wait_byte ; if not 0, repeat h_picture_loop
; jmp comm_init ; filled all memory: reset framebuffer position