AVRFreaks.net

#include <avr32/io.h>
#include "compiler.h"
#include "board.h"
#include "power_clocks_lib.h"
#include "gpio.h"
#include "usart.h"

// comment out whichever channel isn't being used...
//#define TEST_USART         (&AVR32_USART0)
//#define TEST_USART_IRQ      AVR32_USART0_IRQ
#define TEST_USART      (&AVR32_USART1)
#define TEST_USART_IRQ   AVR32_USART1_IRQ

// global vars
int usart_isr_count = 0;
int n = 0;
U8  rxbuff[100];

// USART interrupt service routine
__attribute__((__interrupt__))
static void usart_rx_isr( void )
{
   volatile int rxByte;
   
   usart_isr_count++; // count the interrupts
    rxByte = (TEST_USART->rhr & AVR32_USART_RHR_RXCHR_MASK) >> AVR32_USART_RHR_RXCHR_OFFSET;
   
   rxbuff[n++] = rxByte;
   if(n>99) {
      n = 0; // set a breakpoint here to view buffer
   }
}

int main(void)
{
    pcl_switch_to_osc(PCL_OSC0, FOSC0, OSC0_STARTUP);

    // comment out the two lines to the port not being used below
   static const gpio_map_t USART_GPIO_MAP =
   {
   //{18, 0},   // usart 0 rx mapping
   //{19, 0}    // usart 0 tx mapping
   {24, 0},    // usart 1 rx mapping
   {23, 0}       // usart 1 tx mapping
   };

   // USART options.
   static const usart_options_t USART_OPTIONS =
   {
      .baudrate     = 4800,
      .charlength   = 8,
      .paritytype   = USART_NO_PARITY,
      .stopbits     = USART_1_STOPBIT,
      .channelmode  = USART_NORMAL_CHMODE
   };

   // Assign GPIO to USART.
   gpio_enable_module(USART_GPIO_MAP, sizeof(USART_GPIO_MAP) / sizeof(USART_GPIO_MAP[0]));

   // Disable all interrupts.
    Disable_global_interrupt();
   
   // Initialize interrupt vectors.
    INTC_init_interrupts();
   
   // register interrupt handler
   INTC_register_interrupt(&usart_rx_isr, TEST_USART_IRQ, AVR32_INTC_INT0);

   // Initialize USART in RS232 mode.
   usart_init_rs232(TEST_USART, &USART_OPTIONS, FOSC0);

   TEST_USART->ier = 0x00000001; //AVR32_USART_IER_RXRDY_MASK;

    Enable_global_interrupt();

   while (true); // wait for interrupts on the serial port
}