/*
This project is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Multiprotocol is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with Multiprotocol. If not, see <http://www.gnu.org/licenses/>.
*/
#if defined(FRSKY_RX_CC2500_INO)
#include "iface_cc2500.h"
#define FRSKY_RX_D16FCC_LENGTH 0x1D+1
#define FRSKY_RX_D16LBT_LENGTH 0x20+1
#define FRSKY_RX_D16v2_LENGTH 0x1D+1
#define FRSKY_RX_D8_LENGTH 0x11+1
#define FRSKY_RX_FORMATS 5
enum
{
FRSKY_RX_D8 =0,
FRSKY_RX_D16FCC =1,
FRSKY_RX_D16LBT =2,
FRSKY_RX_D16v2FCC =3,
FRSKY_RX_D16v2LBT =4,
};
enum {
FRSKY_RX_TUNE_START,
FRSKY_RX_TUNE_LOW,
FRSKY_RX_TUNE_HIGH,
FRSKY_RX_BIND,
FRSKY_RX_DATA,
};
const PROGMEM uint8_t FRSKY_RX_common_reg[][2] = {
{CC2500_02_IOCFG0, 0x01},
{CC2500_18_MCSM0, 0x18},
{CC2500_07_PKTCTRL1, 0x05},
{CC2500_3E_PATABLE, 0xFF},
{CC2500_0C_FSCTRL0, 0},
{CC2500_0D_FREQ2, 0x5C},
{CC2500_13_MDMCFG1, 0x23},
{CC2500_14_MDMCFG0, 0x7A},
{CC2500_19_FOCCFG, 0x16},
{CC2500_1A_BSCFG, 0x6C},
{CC2500_1B_AGCCTRL2, 0x03},
{CC2500_1C_AGCCTRL1, 0x40},
{CC2500_1D_AGCCTRL0, 0x91},
{CC2500_21_FREND1, 0x56},
{CC2500_22_FREND0, 0x10},
{CC2500_23_FSCAL3, 0xA9},
{CC2500_24_FSCAL2, 0x0A},
{CC2500_25_FSCAL1, 0x00},
{CC2500_26_FSCAL0, 0x11},
{CC2500_29_FSTEST, 0x59},
{CC2500_2C_TEST2, 0x88},
{CC2500_2D_TEST1, 0x31},
{CC2500_2E_TEST0, 0x0B},
{CC2500_03_FIFOTHR, 0x07},
{CC2500_09_ADDR, 0x03},
};
const PROGMEM uint8_t FRSKY_RX_d16fcc_reg[][2] = {
{CC2500_17_MCSM1, 0x0C},
{CC2500_0E_FREQ1, 0x76},
{CC2500_0F_FREQ0, 0x27},
{CC2500_06_PKTLEN, 0x1E},
{CC2500_08_PKTCTRL0, 0x01},
{CC2500_0B_FSCTRL1, 0x0A},
{CC2500_10_MDMCFG4, 0x7B},
{CC2500_11_MDMCFG3, 0x61},
{CC2500_12_MDMCFG2, 0x13},
{CC2500_15_DEVIATN, 0x51},
};
const PROGMEM uint8_t FRSKY_RX_d16lbt_reg[][2] = {
{CC2500_17_MCSM1, 0x0E},
{CC2500_0E_FREQ1, 0x80},
{CC2500_0F_FREQ0, 0x00},
{CC2500_06_PKTLEN, 0x23},
{CC2500_08_PKTCTRL0, 0x01},
{CC2500_0B_FSCTRL1, 0x08},
{CC2500_10_MDMCFG4, 0x7B},
{CC2500_11_MDMCFG3, 0xF8},
{CC2500_12_MDMCFG2, 0x03},
{CC2500_15_DEVIATN, 0x53},
};
const PROGMEM uint8_t FRSKY_RX_d8_reg[][2] = {
{CC2500_17_MCSM1, 0x0C},
{CC2500_0E_FREQ1, 0x76},
{CC2500_0F_FREQ0, 0x27},
{CC2500_06_PKTLEN, 0x19},
{CC2500_08_PKTCTRL0, 0x05},
{CC2500_0B_FSCTRL1, 0x08},
{CC2500_10_MDMCFG4, 0xAA},
{CC2500_11_MDMCFG3, 0x39},
{CC2500_12_MDMCFG2, 0x11},
{CC2500_15_DEVIATN, 0x42},
};
static uint8_t FRSKY_RX_chanskip;
static int8_t FRSKY_RX_finetune;
static uint8_t FRSKY_RX_format;
static void __attribute__((unused)) FRSKY_RX_strobe_rx()
{
CC2500_Strobe(CC2500_SIDLE);
CC2500_Strobe(CC2500_SFRX);
CC2500_Strobe(CC2500_SRX);
}
static void __attribute__((unused)) FRSKY_RX_initialise_cc2500() {
const uint8_t FRSKY_RX_length[] = { FRSKY_RX_D8_LENGTH, FRSKY_RX_D16FCC_LENGTH, FRSKY_RX_D16LBT_LENGTH, FRSKY_RX_D16v2_LENGTH, FRSKY_RX_D16v2_LENGTH };
packet_length = FRSKY_RX_length[FRSKY_RX_format];
CC2500_Reset();
CC2500_Strobe(CC2500_SIDLE);
for (uint8_t i = 0; i < sizeof(FRSKY_RX_common_reg) / 2; i++)
CC2500_WriteReg(pgm_read_byte_near(&FRSKY_RX_common_reg[i][0]), pgm_read_byte_near(&FRSKY_RX_common_reg[i][1]));
switch (FRSKY_RX_format)
{
case FRSKY_RX_D16v2FCC:
case FRSKY_RX_D16FCC:
for (uint8_t i = 0; i < sizeof(FRSKY_RX_d16fcc_reg) / 2; i++)
CC2500_WriteReg(pgm_read_byte_near(&FRSKY_RX_d16fcc_reg[i][0]), pgm_read_byte_near(&FRSKY_RX_d16fcc_reg[i][1]));
if(FRSKY_RX_format==FRSKY_RX_D16v2FCC)
{
CC2500_WriteReg(CC2500_08_PKTCTRL0, 0x05); // Enable CRC
CC2500_WriteReg(CC2500_17_MCSM1, 0x0E); // Go/Stay in RX mode
CC2500_WriteReg(CC2500_11_MDMCFG3, 0x84); // bitrate 70K->77K
}
break;
case FRSKY_RX_D16v2LBT:
case FRSKY_RX_D16LBT:
for (uint8_t i = 0; i < sizeof(FRSKY_RX_d16lbt_reg) / 2; i++)
CC2500_WriteReg(pgm_read_byte_near(&FRSKY_RX_d16lbt_reg[i][0]), pgm_read_byte_near(&FRSKY_RX_d16lbt_reg[i][1]));
if(FRSKY_RX_format==FRSKY_RX_D16v2LBT)
CC2500_WriteReg(CC2500_08_PKTCTRL0, 0x05); // Enable CRC
break;
case FRSKY_RX_D8:
for (uint8_t i = 0; i < sizeof(FRSKY_RX_d8_reg) / 2; i++)
CC2500_WriteReg(pgm_read_byte_near(&FRSKY_RX_d8_reg[i][0]), pgm_read_byte_near(&FRSKY_RX_d8_reg[i][1]));
CC2500_WriteReg(CC2500_23_FSCAL3, 0x89);
break;
}
CC2500_WriteReg(CC2500_0A_CHANNR, 0); // bind channel
rx_disable_lna = IS_POWER_FLAG_on;
CC2500_SetTxRxMode(rx_disable_lna ? TXRX_OFF : RX_EN); // lna disable / enable
FRSKY_RX_strobe_rx();
delayMicroseconds(1000); // wait for RX to activate
}
static void __attribute__((unused)) FRSKY_RX_set_channel(uint8_t channel)
{
CC2500_WriteReg(CC2500_0A_CHANNR, hopping_frequency[channel]);
if(FRSKY_RX_format == FRSKY_RX_D8)
CC2500_WriteReg(CC2500_23_FSCAL3, 0x89);
CC2500_WriteReg(CC2500_25_FSCAL1, calData[channel]);
FRSKY_RX_strobe_rx();
}
static void __attribute__((unused)) FRSKY_RX_calibrate()
{
FRSKY_RX_strobe_rx();
for (unsigned c = 0; c < 47; c++)
{
CC2500_Strobe(CC2500_SIDLE);
CC2500_WriteReg(CC2500_0A_CHANNR, hopping_frequency[c]);
CC2500_Strobe(CC2500_SCAL);
delayMicroseconds(900);
calData[c] = CC2500_ReadReg(CC2500_25_FSCAL1);
}
}
static uint8_t __attribute__((unused)) frskyx_rx_check_crc_id(bool bind,bool init)
{
/*debugln("RX");
for(uint8_t i=0; i<packet_length;i++)
debug(" %02X",packet[i]);
debugln("");*/
if(bind && packet[0]!=packet_length-1 && packet[1] !=0x03 && packet[2] != 0x01)
return false;
uint8_t offset=bind?3:1;
// Check D8 checksum
if (FRSKY_RX_format == FRSKY_RX_D8)
{
if((packet[packet_length+1] & 0x80) != 0x80) // Check CRC_OK flag in status byte 2
return false; // Bad CRC
if(init)
{//Save TXID
rx_tx_addr[3] = packet[3];
rx_tx_addr[2] = packet[4];
rx_tx_addr[1] = packet[17];
}
else
if(rx_tx_addr[3] != packet[offset] || rx_tx_addr[2] != packet[offset+1] || rx_tx_addr[1] != packet[bind?17:5])
return false; // Bad address
return true; // Full match
}
// Check D16v2 checksum
if (FRSKY_RX_format == FRSKY_RX_D16v2LBT || FRSKY_RX_format == FRSKY_RX_D16v2FCC)
if((packet[packet_length+1] & 0x80) != 0x80) // Check CRC_OK flag in status byte 2
return false;
//debugln("HW Checksum ok");
// Check D16 checksum
uint16_t lcrc = FrSkyX_crc(&packet[3], packet_length - 5); // Compute crc
uint16_t rcrc = (packet[packet_length-2] << 8) | (packet[packet_length-1] & 0xff); // Received crc
if(lcrc != rcrc)
return false; // Bad CRC
//debugln("Checksum ok");
if (bind && (FRSKY_RX_format == FRSKY_RX_D16v2LBT || FRSKY_RX_format == FRSKY_RX_D16v2FCC))
for(uint8_t i=3; i<packet_length-2; i++) //unXOR bind packet
packet[i] ^= 0xA7;
uint8_t offset2=0;
if (bind && (FRSKY_RX_format == FRSKY_RX_D16LBT || FRSKY_RX_format == FRSKY_RX_D16FCC))
offset2=6;
if(init)
{//Save TXID
rx_tx_addr[3] = packet[3];
rx_tx_addr[2] = packet[4];
rx_tx_addr[1] = packet[5+offset2];
rx_tx_addr[0] = packet[6+offset2]; // RXnum
}
else
if(rx_tx_addr[3] != packet[offset] || rx_tx_addr[2] != packet[offset+1] || rx_tx_addr[1] != packet[offset+2+offset2])
return false; // Bad address
//debugln("Address ok");
if(!bind && rx_tx_addr[0] != packet[6])
return false; // Bad RX num
//debugln("Match");
return true; // Full match
}
static void __attribute__((unused)) FRSKY_RX_build_telemetry_packet()
{
uint16_t raw_channel[8];
uint32_t bits = 0;
uint8_t bitsavailable = 0;
uint8_t idx = 0;
uint8_t i;
if (FRSKY_RX_format == FRSKY_RX_D8)
{// decode D8 channels
raw_channel[0] = ((packet[10] & 0x0F) << 8 | packet[6]);
raw_channel[1] = ((packet[10] & 0xF0) << 4 | packet[7]);
raw_channel[2] = ((packet[11] & 0x0F) << 8 | packet[8]);
raw_channel[3] = ((packet[11] & 0xF0) << 4 | packet[9]);
raw_channel[4] = ((packet[16] & 0x0F) << 8 | packet[12]);
raw_channel[5] = ((packet[16] & 0xF0) << 4 | packet[13]);
raw_channel[6] = ((packet[17] & 0x0F) << 8 | packet[14]);
raw_channel[7] = ((packet[17] & 0xF0) << 4 | packet[15]);
for (i = 0; i < 8; i++) {
if (raw_channel[i] < 1290)
raw_channel[i] = 1290;
rx_rc_chan[i] = min(((raw_channel[i] - 1290) << 4) / 15, 2047);
}
}
else
{// decode D16 channels
raw_channel[0] = ((packet[10] << 8) & 0xF00) | packet[9];
raw_channel[1] = ((packet[11] << 4) & 0xFF0) | (packet[10] >> 4);
raw_channel[2] = ((packet[13] << 8) & 0xF00) | packet[12];
raw_channel[3] = ((packet[14] << 4) & 0xFF0) | (packet[13] >> 4);
raw_channel[4] = ((packet[16] << 8) & 0xF00) | packet[15];
raw_channel[5] = ((packet[17] << 4) & 0xFF0) | (packet[16] >> 4);
raw_channel[6] = ((packet[19] << 8) & 0xF00) | packet[18];
raw_channel[7] = ((packet[20] << 4) & 0xFF0) | (packet[19] >> 4);
for (i = 0; i < 8; i++) {
// ignore failsafe channels
if(packet[7] != 0x10+(i<<1)) {
uint8_t shifted = (raw_channel[i] & 0x800)>0;
uint16_t channel_value = raw_channel[i] & 0x7FF;
if (channel_value < 64)
rx_rc_chan[shifted ? i + 8 : i] = 0;
else
rx_rc_chan[shifted ? i + 8 : i] = min(((channel_value - 64) << 4) / 15, 2047);
}
}
}
// buid telemetry packet
packet_in[idx++] = RX_LQI;
packet_in[idx++] = RX_RSSI;
packet_in[idx++] = 0; // start channel
packet_in[idx++] = FRSKY_RX_format == FRSKY_RX_D8 ? 8 : 16; // number of channels in packet
// pack channels
for (i = 0; i < packet_in[3]; i++) {
bits |= ((uint32_t)rx_rc_chan[i]) << bitsavailable;
bitsavailable += 11;
while (bitsavailable >= 8) {
packet_in[idx++] = bits & 0xff;
bits >>= 8;
bitsavailable -= 8;
}
}
}
static void __attribute__((unused)) FRSKY_RX_data()
{
uint16_t temp = FRSKY_RX_EEPROM_OFFSET;
FRSKY_RX_format = eeprom_read_byte((EE_ADDR)temp++) % FRSKY_RX_FORMATS;
rx_tx_addr[3] = eeprom_read_byte((EE_ADDR)temp++);
rx_tx_addr[2] = eeprom_read_byte((EE_ADDR)temp++);
rx_tx_addr[1] = eeprom_read_byte((EE_ADDR)temp++);
rx_tx_addr[0] = RX_num;
FRSKY_RX_finetune = eeprom_read_byte((EE_ADDR)temp++);
debug("format=%d, ", FRSKY_RX_format);
debug("addr[3]=%02X, ", rx_tx_addr[3]);
debug("addr[2]=%02X, ", rx_tx_addr[2]);
debug("addr[1]=%02X, ", rx_tx_addr[1]);
debug("rx_num=%02X, ", rx_tx_addr[0]);
debugln("tune=%d", (int8_t)FRSKY_RX_finetune);
if(FRSKY_RX_format != FRSKY_RX_D16v2LBT && FRSKY_RX_format != FRSKY_RX_D16v2FCC)
{//D8 & D16v1
for (uint8_t ch = 0; ch < 47; ch++)
hopping_frequency[ch] = eeprom_read_byte((EE_ADDR)temp++);
}
else
{
FrSkyFormat=FRSKY_RX_format == FRSKY_RX_D16v2FCC?0:2;
FrSkyX2_init_hop();
}
debug("ch:");
for (uint8_t ch = 0; ch < 47; ch++)
debug(" %02X", hopping_frequency[ch]);
debugln("");
FRSKY_RX_initialise_cc2500();
FRSKY_RX_calibrate();
CC2500_WriteReg(CC2500_18_MCSM0, 0x08); // FS_AUTOCAL = manual
CC2500_WriteReg(CC2500_09_ADDR, rx_tx_addr[3]); // set address
CC2500_WriteReg(CC2500_07_PKTCTRL1, 0x05); // check address
if (option == 0)
CC2500_WriteReg(CC2500_0C_FSCTRL0, FRSKY_RX_finetune);
else
CC2500_WriteReg(CC2500_0C_FSCTRL0, option);
FRSKY_RX_set_channel(hopping_frequency_no);
phase = FRSKY_RX_DATA;
}
void FRSKY_RX_init()
{
if(sub_protocol == FRSKY_ERASE)
{
if(IS_BIND_IN_PROGRESS)
{// Clear all cloned addresses
uint16_t addr[]={ FRSKYD_CLONE_EEPROM_OFFSET+1, FRSKYX_CLONE_EEPROM_OFFSET+1, FRSKYX2_CLONE_EEPROM_OFFSET+1 };
for(uint8_t i=0; i<3;i++)
for(uint8_t j=0; j<3;j++)
eeprom_write_byte((EE_ADDR)(addr[i]+j), 0xFF);
packet_count = 100;
}
}
else
{
FRSKY_RX_chanskip = 1;
hopping_frequency_no = 0;
rx_data_started = false;
FRSKY_RX_finetune = 0;
telemetry_link = 0;
packet_count = 0;
if (IS_BIND_IN_PROGRESS)
{
FRSKY_RX_format = FRSKY_RX_D8;
FRSKY_RX_initialise_cc2500();
phase = FRSKY_RX_TUNE_START;
debugln("FRSKY_RX_TUNE_START");
}
else
FRSKY_RX_data();
}
}
uint16_t FRSKY_RX_callback()
{
static int8_t read_retry = 0;
static int8_t tune_low, tune_high;
uint8_t len, ch;
if(sub_protocol == FRSKY_ERASE)
{
if(packet_count)
packet_count--;
else
BIND_DONE;
return 10000; // Nothing to do...
}
if(IS_BIND_DONE && phase != FRSKY_RX_DATA)
FRSKY_RX_init(); // Abort bind
if ((prev_option != option) && (phase >= FRSKY_RX_DATA))
{
if (option == 0)
CC2500_WriteReg(CC2500_0C_FSCTRL0, FRSKY_RX_finetune);
else
CC2500_WriteReg(CC2500_0C_FSCTRL0, option);
prev_option = option;
}
if (rx_disable_lna != IS_POWER_FLAG_on)
{
rx_disable_lna = IS_POWER_FLAG_on;
CC2500_SetTxRxMode(rx_disable_lna ? TXRX_OFF : RX_EN);
}
len = CC2500_ReadReg(CC2500_3B_RXBYTES | CC2500_READ_BURST) & 0x7F;
switch(phase)
{
case FRSKY_RX_TUNE_START:
if (len == packet_length + 2) //+2=RSSI+LQI+CRC
{
CC2500_ReadData(packet, len);
if(frskyx_rx_check_crc_id(true,true))
{
FRSKY_RX_finetune = -127;
CC2500_WriteReg(CC2500_0C_FSCTRL0, FRSKY_RX_finetune);
phase = FRSKY_RX_TUNE_LOW;
debugln("FRSKY_RX_TUNE_LOW");
FRSKY_RX_strobe_rx();
state = 0;
return 1000;
}
}
FRSKY_RX_format = (FRSKY_RX_format + 1) % FRSKY_RX_FORMATS; // switch to next format (D8, D16FCC, D16LBT, D16v2FCC, D16v2LBT)
FRSKY_RX_initialise_cc2500();
FRSKY_RX_finetune += 10;
CC2500_WriteReg(CC2500_0C_FSCTRL0, FRSKY_RX_finetune);
FRSKY_RX_strobe_rx();
return 18000;
case FRSKY_RX_TUNE_LOW:
if (len == packet_length + 2) //+2=RSSI+LQI+CRC
{
CC2500_ReadData(packet, len);
if(frskyx_rx_check_crc_id(true,false)) {
tune_low = FRSKY_RX_finetune;
FRSKY_RX_finetune = 127;
CC2500_WriteReg(CC2500_0C_FSCTRL0, FRSKY_RX_finetune);
phase = FRSKY_RX_TUNE_HIGH;
debugln("FRSKY_RX_TUNE_HIGH");
FRSKY_RX_strobe_rx();
return 1000;
}
}
FRSKY_RX_finetune += 1;
CC2500_WriteReg(CC2500_0C_FSCTRL0, FRSKY_RX_finetune);
FRSKY_RX_strobe_rx();
return 18000;
case FRSKY_RX_TUNE_HIGH:
if (len == packet_length + 2) //+2=RSSI+LQI+CRC
{
CC2500_ReadData(packet, len);
if(frskyx_rx_check_crc_id(true,false)) {
tune_high = FRSKY_RX_finetune;
FRSKY_RX_finetune = (tune_low + tune_high) / 2;
CC2500_WriteReg(CC2500_0C_FSCTRL0, (int8_t)FRSKY_RX_finetune);
if(tune_low < tune_high)
{
phase = FRSKY_RX_BIND;
debugln("FRSKY_RX_TUNE_HIGH");
}
else
{
phase = FRSKY_RX_TUNE_START;
debugln("FRSKY_RX_TUNE_START");
}
FRSKY_RX_strobe_rx();
return 1000;
}
}
FRSKY_RX_finetune -= 1;
CC2500_WriteReg(CC2500_0C_FSCTRL0, FRSKY_RX_finetune);
FRSKY_RX_strobe_rx();
return 18000;
case FRSKY_RX_BIND:
if (len == packet_length + 2) //+2=RSSI+LQI+CRC
{
CC2500_ReadData(packet, len);
if(frskyx_rx_check_crc_id(true,false)) {
if(FRSKY_RX_format != FRSKY_RX_D16v2LBT && FRSKY_RX_format != FRSKY_RX_D16v2FCC)
{// D8 & D16v1
if(packet[5] <= 0x2D)
{
for (ch = 0; ch < 5; ch++)
hopping_frequency[packet[5]+ch] = packet[6+ch];
state |= 1 << (packet[5] / 5);
}
}
else
state = 0x3FF; //No hop table for D16v2
if (state == 0x3FF)
{
debugln("Bind complete");
BIND_DONE;
// store format, finetune setting, txid, channel list
uint16_t temp = FRSKY_RX_EEPROM_OFFSET;
if(sub_protocol==FRSKY_CLONE)
{
if(FRSKY_RX_format==FRSKY_RX_D8)
temp=FRSKYD_CLONE_EEPROM_OFFSET;
else if(FRSKY_RX_format == FRSKY_RX_D16FCC || FRSKY_RX_format == FRSKY_RX_D16LBT)
temp=FRSKYX_CLONE_EEPROM_OFFSET;
else
temp=FRSKYX2_CLONE_EEPROM_OFFSET;
}
eeprom_write_byte((EE_ADDR)temp++, FRSKY_RX_format);
eeprom_write_byte((EE_ADDR)temp++, rx_tx_addr[3]);
eeprom_write_byte((EE_ADDR)temp++, rx_tx_addr[2]);
eeprom_write_byte((EE_ADDR)temp++, rx_tx_addr[1]);
if(sub_protocol == FRSKY_RX || sub_protocol == FRSKY_CPPM) // FRSKY_RX, FRSKY_CPPM
eeprom_write_byte((EE_ADDR)temp++, FRSKY_RX_finetune);
if(FRSKY_RX_format != FRSKY_RX_D16v2FCC && FRSKY_RX_format != FRSKY_RX_D16v2LBT)
for (ch = 0; ch < 47; ch++)
eeprom_write_byte((EE_ADDR)temp++, hopping_frequency[ch]);
FRSKY_RX_data();
debugln("FRSKY_RX_DATA");
}
}
FRSKY_RX_strobe_rx();
}
return 1000;
case FRSKY_RX_DATA:
if (len == packet_length + 2) //+2=RSSI+LQI+CRC
{
CC2500_ReadData(packet, len);
if(frskyx_rx_check_crc_id(false,false))
{
RX_RSSI = packet[len-2];
if(RX_RSSI >= 128)
RX_RSSI -= 128;
else
RX_RSSI += 128;
bool chanskip_valid=true;
// hop to next channel
if (FRSKY_RX_format != FRSKY_RX_D8)
{//D16v1 & D16v2
if(rx_data_started)
{
if(FRSKY_RX_chanskip != (((packet[4] & 0xC0) >> 6) | ((packet[5] & 0x3F) << 2)))
{
chanskip_valid=false; // chanskip value has changed which surely indicates a bad frame
packet_count++;
if(packet_count>5) // the TX must have changed chanskip...
FRSKY_RX_chanskip = ((packet[4] & 0xC0) >> 6) | ((packet[5] & 0x3F) << 2); // chanskip init
}
else
packet_count=0;
}
else
FRSKY_RX_chanskip = ((packet[4] & 0xC0) >> 6) | ((packet[5] & 0x3F) << 2); // chanskip init
}
hopping_frequency_no = (hopping_frequency_no + FRSKY_RX_chanskip) % 47;
FRSKY_RX_set_channel(hopping_frequency_no);
if(chanskip_valid)
{
if ((telemetry_link & 0x7F) == 0)
{ // send channels to TX
FRSKY_RX_build_telemetry_packet();
telemetry_link = 1;
#ifdef SEND_CPPM
if(sub_protocol == FRSKY_CPPM)
telemetry_link |= 0x80; // Disable telemetry output
#endif
}
pps_counter++;
}
rx_data_started = true;
read_retry = 0;
}
}
// packets per second
if (millis() - pps_timer >= 1000) {
pps_timer = millis();
debugln("%d pps", pps_counter);
RX_LQI = pps_counter;
if(pps_counter==0) // no packets for 1 sec or more...
{// restart the search
rx_data_started=false;
packet_count=0;
}
pps_counter = 0;
}
// skip channel if no packet received in time
if (read_retry++ >= 9) {
hopping_frequency_no = (hopping_frequency_no + FRSKY_RX_chanskip) % 47;
FRSKY_RX_set_channel(hopping_frequency_no);
if(rx_data_started)
read_retry = 0;
else
read_retry = -50; // retry longer until first packet is catched
}
break;
}
return 1000;
}
#endif