I used the RS232 serial communication protocol, so I bought MAX232 to generate RS232 logiv form (+8,5 for '1' and -8,5 for '0'), converted from AVR's output. The USART communication will be the good choice.
I've display the ASCII character saved in AVR's .db directive to the hyperterminal window.
I plan to build datalogger, visual interface. The graphic will show the AVR's ADC value for some sampled time, using Borland Delphi 6.
So, this is my code, in assembler :
I've display the ASCII character saved in AVR's .db directive to the hyperterminal window.
I plan to build datalogger, visual interface. The graphic will show the AVR's ADC value for some sampled time, using Borland Delphi 6.
So, this is my code, in assembler :
| CODE |
.include "m8535def.inc" .cseg .org 0 rjmp main main: ldi tmp,low(ramend) out spl,tmp ldi tmp,high(ramend) out sph,tmp rcall init_usart loop: ldi zl,low(2*msg) ldi zh,high(2*msg) load: lpm mov txbyte,r0 cpi txbyte,0 breq done rcall usart_tx inc zl rjmp load done: rcall usart_rx mov txbyte,rxbyte rcall usart_tx rjmp done .include "C:\Program Files\Atmel\AVR Tools\AvrStudio4\usart3\usart_lib.asm" msg: .db "***dicoba 1, 2, 3 ...***",13,10,0 and the included file : ;==================================== ;USART Library for ATMEGA8535 ;==================================== ;============= ; usart init ;============= ;===================================== ; konfigurasi usart ;===================================== .def tmp = r16 .def txbyte = r17 .def rxbyte = r18 .equ fclock = 11059200 .equ baud_rate = 9600 .equ ubbr_value = (fclock/(16*baud_rate)) - 1 init_usart: ; Set baud rate ldi tmp,high(ubbr_value) out UBRRH, tmp ldi tmp,low(ubbr_value) out UBRRL, tmp ; Enable Receiver and Transmitter ldi tmp, 0b00011000 out UCSRB,tmp ; Set frame format: 8data, 1stop bit ldi tmp, 0b10000110 out UCSRC,tmp ret ;===================== ; usart transmit data ;===================== usart_tx: ; Wait for empty transmit buffer sbis UCSRA,UDRE rjmp usart_tx ; Put data into buffer, sends the data out UDR,txbyte ret ;====================== ; usart receive data ;====================== usart_rx: ; Wait for data to be received sbis UCSRA, RXC rjmp usart_rx ; Get and return received data from buffer in rxbyte, UDR ret ;======================= ; newline ;======================= newline: ldi txbyte,13 rcall usart_tx ldi txbyte,10 rcall usart_tx ret |