This example shows, how frames are received and their CRCR16 is checked in software.
#include "board.h"
#include "transceiver.h"
#include "ioutil.h"
#include <util/crc16.h>
#include "xmpl.h"
static volatile uint8_t rxcnt;
int main(void)
{
ERR_CHECK(TRX_OFF!=rval);
#if defined(TRX_IRQ_TRX_END)
#elif defined(TRX_IRQ_RX_END)
#else
# error "Unknown IRQ bits"
#endif
rxcnt = 0;
while(1);
}
#if defined(TRX_IF_RFA1)
ISR(TRX24_RX_END_vect)
{
uint8_t flen, *pfrm;
uint16_t crc;
pfrm = rxfrm;
crc = 0;
do
{
crc = _crc_ccitt_update(crc, *pfrm++);
}
while(flen--);
if (crc == 0)
{
rxcnt ++;
}
}
#else
ISR(TRX_IRQ_vect)
{
uint8_t flen, *pfrm, tmp;
uint16_t crc;
if (irq_cause & TRX_IRQ_TRX_END)
{
pfrm = rxfrm;
crc = 0;
do
{
crc = _crc_ccitt_update(crc, *pfrm++);
}
while(flen--);
if (crc == 0)
{
rxcnt ++;
}
}
}
#endif