altera_avalon_i2c_slave.c

i2c从设备的源码

#include<altera_avalon_i2c_slave.h>

static int * i2c_slave_base;

static char  rx_byte;
static int   rx_available;

void alt_i2c_slave_init(int * i2c_slave_base_address, int i2c_slave_irq_no,char i2c_address){
  
  i2c_slave_base = i2c_slave_base_address;
  
  IOWR_ALTERA_AVALON_I2C_SLAVE_ADDRESS((int)i2c_slave_base, i2c_address); // set the address value
  
  alt_irq_register(i2c_slave_irq_no,(void *)0x0,alt_i2c_slave_isr); // register the ISR
  
  IOWR_ALTERA_AVALON_I2C_SLAVE_INTERRUPT_MASK((int)i2c_slave_base, 1); // enable interrupts and return
}

void alt_i2c_slave_isr(void * context, alt_u32 irq){
  
  IOWR_ALTERA_AVALON_I2C_SLAVE_INTERRUPT(i2c_slave_base,0x0); // clear the interrupt
  
  rx_byte = IORD_ALTERA_AVALON_I2C_SLAVE_DATA((int)i2c_slave_base);
  rx_available = 1;
}

int alt_i2c_slave_rx_available(void){
  return(rx_available);
}

char alt_i2c_slave_recieve(void){
  rx_available = 0;
  return(rx_byte);
}

char alt_i2c_slave_transmit(char data){
	IOWR_ALTERA_AVALON_I2C_SLAVE_DATA((int)i2c_slave_base, data);
}