test_scom.c

AVR单片机开发的键盘处理程序C源代码希望对单片机初学选手有点帮助

//ICC-AVR application builder : 2004-8-25 1:33
// Target : M16
// Crystal: 8.0000Mhz

#include <iom16v.h>
#include <macros.h>

void port_init(void)
{
 PORTA = 0xFF;
 DDRA  = 0x00;
 PORTB = 0xFF;
 DDRB  = 0x00;
 PORTC = 0xFF; //m103 output only
 DDRC  = 0x00;
 PORTD = 0xFF;
 DDRD  = 0x00;
}

//UART0 initialisation
// desired baud rate: 9600
// actual: baud rate:9615 (0.2%)
// char size: 8 bit
// parity: Disabled
void uart0_init(void)
{
 UCSRB = 0x00; //disable while setting baud rate
 UCSRA = 0x00;
 UCSRC = 0x86;
 UBRRL = 0x00; //set baud rate lo
 UBRRH = 0x00; //set baud rate hi
 UCSRB = 0x98;
}

#pragma interrupt_handler uart0_rx_isr:12
void uart0_rx_isr(void)
{
 //uart has received a character in UDR
}

//call this routine to initialise all peripherals
void init_devices(void)
{
 //stop errant interrupts until set up
 CLI(); //disable all interrupts
 port_init();
 uart0_init();

 MCUCR = 0x00;
 GICR  = 0x00;
 TIMSK = 0x00; //timer interrupt sources
 SEI(); //re-enable interrupts
 //all peripherals are now initialised
}

//
void main(void)
{
 init_devices();
 //insert your functional code here...
}