bool cc2538_channel_clear(void)
{
if (RFCORE->XREG_FSMSTAT0bits.FSM_FFCTRL_STATE == FSM_STATE_IDLE) {
bool result;
cc2538_on();
RFCORE_WAIT_UNTIL(RFCORE->XREG_RSSISTATbits.RSSI_VALID);
result = BOOLEAN(RFCORE->XREG_FSMSTAT1bits.CCA);
cc2538_off();
return result;
}
else {
RFCORE_WAIT_UNTIL(RFCORE->XREG_RSSISTATbits.RSSI_VALID);
return BOOLEAN(RFCORE->XREG_FSMSTAT1bits.CCA);
}
}
static int _send(netdev_t *netdev, const iolist_t *iolist)
{
(void) netdev;
int pkt_len = 0;
/* Flush TX FIFO once no transmission in progress */
RFCORE_WAIT_UNTIL(RFCORE->XREG_FSMSTAT1bits.TX_ACTIVE == 0);
RFCORE_SFR_RFST = ISFLUSHTX;
/* The first byte of the TX FIFO must be the packet length,
but we don't know what it is yet. Write a null byte to the
start of the FIFO, so we can come back and update it later */
rfcore_write_byte(0);
for (const iolist_t *iol = iolist; iol; iol = iol->iol_next) {
pkt_len += iol->iol_len;
if (pkt_len > CC2538_RF_MAX_DATA_LEN) {
DEBUG("cc2538_rf: packet too large (%u > %u)\n",
pkt_len, CC2538_RF_MAX_DATA_LEN);
return -EOVERFLOW;
}
rfcore_write_fifo(iol->iol_base, iol->iol_len);
}
#ifdef MODULE_NETSTATS_L2
netdev->stats.tx_bytes += pkt_len;
#endif
/* Set first byte of TX FIFO to the packet length */
rfcore_poke_tx_fifo(0, pkt_len + CC2538_AUTOCRC_LEN);
RFCORE_SFR_RFST = ISTXON;
/* Wait for transmission to complete */
RFCORE_WAIT_UNTIL(RFCORE->XREG_FSMSTAT1bits.TX_ACTIVE == 0);
return pkt_len;
}
void cc2538_off(void)
{
/* Wait for ongoing TX to complete (e.g. this could be an outgoing ACK) */
RFCORE_WAIT_UNTIL(RFCORE->XREG_FSMSTAT1bits.TX_ACTIVE == 0);
/* Flush RX FIFO */
RFCORE_SFR_RFST = ISFLUSHRX;
/* Don't turn off if we are off as this will trigger a Strobe Error */
if (RFCORE_XREG_RXENABLE != 0) {
RFCORE_SFR_RFST = ISRFOFF;
}
}
