mirror of
https://github.com/sergeyyarkov/attiny2313a_shift-register-example.git
synced 2026-10-11 02:08:50 +03:00
137 lines
4.1 KiB
NASM
137 lines
4.1 KiB
NASM
;
|
|
; Project name: shift-register-example
|
|
; Description: An example of using the single 74HC595 shift register with an AVR microcontroller
|
|
; Source code: https://github.com/sergeyyarkov/attiny2313a_shift-register-example
|
|
; Device: ATtiny2313A
|
|
; Device Datasheet: http://ww1.microchip.com/downloads/en/DeviceDoc/doc8246.pdf
|
|
; Package: SOIC-20W_7.5x12.8mm_P1.27mm
|
|
; Assembler: AVR macro assembler 2.2.7
|
|
; Clock frequency: 12 MHz External Crystal Oscillator
|
|
; Fuses: lfuse: 0x4F, hfuse: 0x9F, efuse: 0xFF, lock: 0xFF
|
|
;
|
|
; Written by Sergey Yarkov 22.01.2023
|
|
|
|
.INCLUDE "tn2313Adef.inc"
|
|
.LIST
|
|
|
|
.DEF COUNTER = r20
|
|
|
|
;========================================;
|
|
; LABELS ;
|
|
;========================================;
|
|
|
|
.EQU CLOCK_PIN = PB0 ; ST_CP on 74HC595
|
|
.EQU DATA_PIN = PB1 ; DS on 74HC595
|
|
.EQU LATCH_PIN = PB2 ; SH_CP on 74HC595
|
|
|
|
;========================================;
|
|
; CODE SEGMENT ;
|
|
;========================================;
|
|
|
|
.CSEG
|
|
.ORG 0x00
|
|
|
|
;========================================;
|
|
; VECTORS ;
|
|
;========================================;
|
|
|
|
rjmp RESET_vect ; Program start at RESET vector
|
|
;reti ; External Interrupt Request 0 / inactive
|
|
;reti ; External Interrupt Request 1 / inactive
|
|
;reti ; Timer/Counter1 Capture Event / inactive
|
|
;reti ; Timer/Counter1 Compare Match A / inactive
|
|
;reti ; Timer/Counter1 Overflow / inactive
|
|
;reti ; Timer/Counter0 Overflow / inactive
|
|
;reti ; USART0, Rx Complete / inactive
|
|
;reti ; USART0 Data Register Empty / inactive
|
|
;reti ; USART0, Tx Complete / inactive
|
|
;reti ; Analog Comparator / inactive
|
|
;reti ; Pin Change Interrupt Request 0/ inactive
|
|
;reti ; Timer/Counter1 Compare Match B / inactive
|
|
;reti ; Timer/Counter0 Compare Match A / inactive
|
|
;reti ; Timer/Counter0 Compare Match B / inactive
|
|
;reti ; USI Start Condition/ inactive
|
|
;reti ; USI Overflow / inactive
|
|
;reti ; EEPROM Ready/ inactive
|
|
;reti ; Watchdog Timer Overflow / inactive
|
|
;reti ; Pin Change Interrupt Request 1 / inactive
|
|
;reti ; Pin Change Interrupt Request 2 / inactive
|
|
|
|
RESET_vect:
|
|
;========================================;
|
|
; INITIALIZE STACK POINTER ;
|
|
;========================================;
|
|
ldi r16, low(RAMEND)
|
|
out SPL, r16
|
|
|
|
MCU_INIT:
|
|
rcall INIT_PORTS
|
|
|
|
ldi COUNTER, 0
|
|
rjmp LOOP
|
|
|
|
INIT_PORTS:
|
|
ldi r16, (1<<CLOCK_PIN) | (1<<LATCH_PIN) | (1<<DATA_PIN)
|
|
out DDRB, r16
|
|
ret
|
|
|
|
;========================================;
|
|
; SEND BYTE TO 74HC595 ;
|
|
;========================================;
|
|
TRANSMIT_595:
|
|
push r19
|
|
mov r19, COUNTER
|
|
ldi r16, 8
|
|
_TRANSMIT_595_LOOP:
|
|
lsl r19
|
|
brcc _TRANSMIT_595_SEND_LOW
|
|
brcs _TRANSMIT_595_SEND_HIGH
|
|
|
|
_TRANSMIT_595_SEND_HIGH:
|
|
sbi PORTB, DATA_PIN
|
|
rjmp _TRANSMIT_595_COMMIT
|
|
|
|
_TRANSMIT_595_SEND_LOW:
|
|
cbi PORTB, DATA_PIN
|
|
|
|
_TRANSMIT_595_COMMIT:
|
|
sbi PORTB, CLOCK_PIN
|
|
cbi PORTB, CLOCK_PIN
|
|
sbi PORTB, LATCH_PIN
|
|
cbi PORTB, LATCH_PIN
|
|
dec r16
|
|
brne _TRANSMIT_595_LOOP
|
|
pop r19
|
|
ret
|
|
|
|
;========================================;
|
|
; MAIN PROGRAM LOOP ;
|
|
;========================================;
|
|
|
|
LOOP:
|
|
rcall TRANSMIT_595
|
|
inc COUNTER
|
|
rcall DELAY
|
|
rjmp LOOP
|
|
|
|
DELAY:
|
|
push r16
|
|
push r17
|
|
cli
|
|
ldi r16, 20
|
|
_DELAY_1:
|
|
ldi r17, 255
|
|
_DELAY_2:
|
|
dec r17
|
|
nop
|
|
nop
|
|
nop
|
|
brne _DELAY_2
|
|
|
|
dec r16
|
|
brne _DELAY_1
|
|
sei
|
|
|
|
pop r17
|
|
pop r16
|
|
ret |