u8 XN297_ReadPayload(u8* msg, int len)
{
// TODO: if xn297_crc==1, check CRC before filling *msg
u8 res = NRF24L01_ReadPayload(msg, len);
for(u8 i=0; i<len; i++)
msg[i] = bit_reverse(msg[i])^bit_reverse(xn297_scramble[i+xn297_addr_len]);
return res;
}
bool NRF24L01_ReadPayloadIfAvailable(uint8_t *data, uint8_t length)
{
if (NRF24L01_ReadReg(NRF24L01_17_FIFO_STATUS) & BV(NRF24L01_17_FIFO_STATUS_RX_EMPTY)) {
return false;
}
NRF24L01_ReadPayload(data, length);
return true;
}
uint8_t XN297_ReadPayload(uint8_t* msg, int len)
{
uint8_t res = NRF24L01_ReadPayload(msg, len);
uint8_t i;
for(i = 0; i<len; i++)
msg[i] = bit_reverse(msg[i]) ^ bit_reverse(xn297_scramble[i+xn297_addr_len]);
return res;
}
static rx_spi_received_e readrx(uint8_t *packet)
{
if (!(NRF24L01_ReadReg(NRF24L01_07_STATUS) & BV(NRF24L01_07_STATUS_RX_DR))) {
uint32_t t = micros() - packet_timer;
if (t > rx_timeout) {
switch_channel();
packet_timer = micros();
}
return RX_SPI_RECEIVED_NONE;
}
packet_timer = micros();
NRF24L01_WriteReg(NRF24L01_07_STATUS, BV(NRF24L01_07_STATUS_RX_DR)); // clear the RX_DR flag
NRF24L01_ReadPayload(packet, V2X2_PAYLOAD_SIZE);
NRF24L01_FlushRx();
switch_channel();
return decode_packet(packet);
}
static u8 packet_ack()
{
if (++dbg_cnt > 50) {
dbgprintf("S: %02x\n", NRF24L01_ReadReg(NRF24L01_07_STATUS));
dbg_cnt = 0;
}
switch (NRF24L01_ReadReg(NRF24L01_07_STATUS) & (BV(NRF24L01_07_TX_DS) | BV(NRF24L01_07_MAX_RT))) {
case BV(NRF24L01_07_TX_DS):
rx_payload_len = NRF24L01_GetDynamicPayloadSize();
if (rx_payload_len > MAX_PACKET_SIZE) {
rx_payload_len = MAX_PACKET_SIZE;
}
NRF24L01_ReadPayload(rx_packet, rx_payload_len);
return PKT_ACKED;
case BV(NRF24L01_07_MAX_RT):
return PKT_TIMEOUT;
}
return PKT_PENDING;
}
void readrx(void)
{
int chan;
uint16_t data[8];
if (!(NRF24L01_ReadReg(NRF24L01_07_STATUS) & BV(NRF24L01_07_RX_DR))) {
uint32_t t = lib_timers_gettimermicroseconds(packet_timer);
if (t > rx_timeout) {
if (boundprotocol != PROTO_NONE) {
if (++missed_packets > 500 && bind_phase == PHASE_JUST_BOUND) {
valid_packets = missed_packets = bad_packets = 0;
bind_phase = PHASE_LOST_BINDING;
prepare_to_bind();
}
} else switch_channel();
packet_timer = lib_timers_starttimer();
}
return;
}
packet_timer = lib_timers_starttimer();
NRF24L01_WriteReg(NRF24L01_07_STATUS, BV(NRF24L01_07_RX_DR));
NRF24L01_ReadPayload(packet, V2X2_PAYLOAD_SIZE);
NRF24L01_FlushRx();
switch_channel();
if (!decode_packet(packet, data))
return;
for (chan = 0; chan < 8; ++chan) {
// data = pwmRead(chan);
// if (data < 750 || data > 2250)
// data = 1500;
// convert from 1000-2000 range to -1 to 1 fixedpointnum range and low pass filter to remove glitches
lib_fp_lowpassfilter(&global.rxvalues[chan], ((fixedpointnum) data[chan] - 1500) * 131L, global.timesliver, FIXEDPOINTONEOVERONESIXTYITH, TIMESLIVEREXTRASHIFT);
}
// reset the failsafe timer
global.failsafetimer = lib_timers_starttimer();
}
u16 ASSAN_callback()
{
switch (state)
{
// Bind
case BIND0:
//Config RX @1M
NRF24L01_WriteReg(NRF24L01_05_RF_CH, RF_BIND_CHANNEL);
NRF24L01_SetBitrate(NRF24L01_BR_1M); // 1Mbps
NRF24L01_SetTxRxMode(RX_EN);
state = BIND1;
/* FALLTHROUGH */
case BIND1:
//Wait for receiver to send the frames
if( NRF24L01_ReadReg(NRF24L01_07_STATUS) & BV(NRF24L01_07_RX_DR))
{ //Something has been received
NRF24L01_ReadPayload(packet, PACKET_SIZE);
if(packet[19]==0x13)
{ //Last frame received
state = BIND2 | WAIT;
//Switch to TX
NRF24L01_SetTxRxMode(TXRX_OFF);
NRF24L01_SetTxRxMode(TX_EN);
//Prepare bind packet
memset(packet,0x05,PACKET_SIZE-5);
packet[15]=0x99;
for(u8 i=0;i<4;i++)
packet[16+i]=packet[23-i];
packet_count=0;
return 10000;
}
}
return 1000;
case BIND2|WAIT:
if(++packet_count == 27) // Wait 270ms in total...
{
packet_count = 0;
state &= ~WAIT;
}
return 10000;
case BIND2:
// Send 20 packets
packet_count++;
if(packet_count==20)
packet[15]=0x13; // different value for last packet
NRF24L01_WritePayload(packet, PACKET_SIZE);
if(packet_count==20)
{
state = DATA0 | WAIT;
packet_count = 0;
}
return 22520;
case DATA0|WAIT:
if(++packet_count == 217)
state &= ~WAIT;
return 10000;
// Normal operation
case DATA0:
// Bind Done
PROTOCOL_SetBindState(0);
NRF24L01_SetBitrate(NRF24L01_BR_250K); // 250Kbps
NRF24L01_SetTxRxMode(TXRX_OFF);
NRF24L01_SetTxRxMode(TX_EN);
/* FALLTHROUGH */
case DATA1:
case DATA4:
// Change ID and RF channel
NRF24L01_WriteRegisterMulti(NRF24L01_10_TX_ADDR, packet+20+4*hopping_frequency_no, ADDRESS_LENGTH);
NRF24L01_WriteReg(NRF24L01_05_RF_CH, hopping_frequency[hopping_frequency_no]);
hopping_frequency_no^=0x01;
state=DATA2;
return 2000;
case DATA2:
case DATA3:
send_packet();
state++; // DATA 3 or 4
return 5000;
}
return 0;
}
