{

/* There was a bug in A1 hardware that will not handle 1 byte commands.

It was supposedly fixed in B0 but the fix didn't make it at the last minute, so here we go again */

if (byteCountTx == 1)

byteCountTx++;

digitalWrite(SSpin,LOW);

char answer;

// Serial.print("sent: ");

// for (int j = 0; j < byteCountTx; j++) // Loop through the bytes of the pData

// {

// byte wordb = pData[j];

// Serial.print(wordb,HEX);

// Serial.print(" ");

// }

// Serial.println();

for (int j = 0; j < byteCountTx; j++) // Loop through the bytes of the pData

{

byte wordb = pData[j];

SPI.transfer(wordb);

}

digitalWrite(SSpin,HIGH);

delayMicroseconds(20);

digitalWrite(SSpin,LOW);

int reply = 0x00;

while (reply != 0xFF)

{

reply = SPI.transfer(0x44);

// Serial.print(reply,HEX);

// Serial.print(" ");

if (reply != 0xFF)

{

digitalWrite(SSpin,HIGH);

delayMicroseconds(20);

digitalWrite(SSpin,LOW);

}

}

// Serial.println();

// Serial.print("rx: ");

// for (int k = 1; k < byteCountRx; k++)

// {

// Serial.print(SPI.transfer(0x44), HEX);

// Serial.print(" ");

// }

digitalWrite(SSpin,HIGH);

// Serial.println();

delay(200); // Wait half a second to prevent Serial buffer overflow

{

digitalWrite(VCXO_ENABLE_PIN,HIGH);

// Serial.println("VCXO is enabled");

delay(200);

digitalWrite(RADIO_SDN_PIN, HIGH); // active high shutdown = reset

delay(200);

digitalWrite(RADIO_SDN_PIN, LOW); // booting

// Serial.println("Radio is powered up");

// Start talking to the Si446X radio chip

const char PART_INFO_command[] = {0x01}; // Part Info

SendCmdReceiveAnswer(1, 9, PART_INFO_command);

// Serial.println("Part info was checked");

//divide VCXO_FREQ into its bytes; MSB first

unsigned int x3 = VCXO_FREQ / 0x1000000;

unsigned int x2 = (VCXO_FREQ - x3 * 0x1000000) / 0x10000;

unsigned int x1 = (VCXO_FREQ - x3 * 0x1000000 - x2 * 0x10000) / 0x100;

unsigned int x0 = (VCXO_FREQ - x3 * 0x1000000 - x2 * 0x10000 - x1 * 0x100);

//POWER_UP

const char init_command[] = {0x02, 0x01, 0x01, x3, x2, x1, x0};// no patch, boot main app. img, FREQ_VCXO, return 1 byte

SendCmdReceiveAnswer(7, 1 ,init_command);

// Serial.println("Radio booted");

const char get_int_status_command[] = {0x20, 0x00, 0x00, 0x00}; // Clear all pending interrupts and get the interrupt status back

SendCmdReceiveAnswer(4, 9, get_int_status_command);

// Serial.println("Radio ready");

const char gpio_pin_cfg_command[] = {0x13, 0x02, 0x02, 0x02, 0x02, 0x08, 0x11, 0x00}; // Set all GPIOs LOW; Link NIRQ to CTS; Link SDO to MISO; Max drive strength

SendCmdReceiveAnswer(8, 8, gpio_pin_cfg_command);

// Serial.println("LEDs should be switched off at this point");

setFrequency(active_freq);

// Serial.println("Frequency set");

setModem();

// Serial.println("CW mode set");

tune_tx();

// Serial.println("TX tune");

{

char change_state_command[] = {0x34, 0x07}; // Change to TX state

SendCmdReceiveAnswer(2, 1, change_state_command);

{

char change_state_command[] = {0x34, 0x03}; // Change to Ready state

SendCmdReceiveAnswer(2, 1, change_state_command);

{

char change_state_command[] = {0x34, 0x05}; // Change to TX tune state

SendCmdReceiveAnswer(2, 1, change_state_command);

{

// Set to CW mode

// Serial.println("Setting modem into CW mode");

char set_modem_mod_type_command[] = {0x11, 0x20, 0x01, 0x00, 0x00};

SendCmdReceiveAnswer(5, 1, set_modem_mod_type_command);

{

// Set the output divider according to recommended ranges given in Si446x datasheet

int outdiv = 4;

int band = 0;

if (freq < 705000000UL) { outdiv = 6; band = 1;};

if (freq < 525000000UL) { outdiv = 8; band = 2;};

if (freq < 353000000UL) { outdiv = 12; band = 3;};

if (freq < 239000000UL) { outdiv = 16; band = 4;};

if (freq < 177000000UL) { outdiv = 24; band = 5;};

unsigned long f_pfd = 2 * VCXO_FREQ / outdiv;

unsigned int n = ((unsigned int)(freq / f_pfd)) - 1;

float ratio = (float)freq / (float)f_pfd;

float rest = ratio - (float)n;

unsigned long m = (unsigned long)(rest * 524288UL);

// set the band parameter

unsigned int sy_sel = 8; //

char set_band_property_command[] = {0x11, 0x20, 0x01, 0x51, (band + sy_sel)}; //

// send parameters

SendCmdReceiveAnswer(5, 1, set_band_property_command);

// Set the pll parameters

unsigned int m2 = m / 0x10000;

unsigned int m1 = (m - m2 * 0x10000) / 0x100;

unsigned int m0 = (m - m2 * 0x10000 - m1 * 0x100);

// assemble parameter string

char set_frequency_property_command[] = {0x11, 0x40, 0x04, 0x00, n, m2, m1, m0};

// send parameters

SendCmdReceiveAnswer(8, 1, set_frequency_property_command);

{

// Not much radio configuration to do here

// because we initialize the transmitter each time right before we transmit a packet

// Just make sure that the VCXO is on and the transmitter chip is switched off at boot up

pinMode(VCXO_ENABLE_PIN, OUTPUT);

digitalWrite(VCXO_ENABLE_PIN,HIGH);

Serial.println("VCXO is enabled");

pinMode(RADIO_SDN_PIN, OUTPUT);

delay(300);

digitalWrite(RADIO_SDN_PIN, HIGH); // active high = shutdown

// Set up SPI

pinMode(SCKpin, OUTPUT);

pinMode(SSpin, OUTPUT);

pinMode(MOSIpin, OUTPUT);

digitalWrite(SSpin, HIGH); // ensure SS stays high for now

// initialize SPI:

SPI.begin();

SPI.setDataMode(SPI_MODE0);

SPI.setBitOrder(MSBFIRST);

SPI.setClockDivider(SPI_CLOCK_DIV8); // 8 MHz / 8 = 1 MHz

delay(200);

// Serial.println("SPI is initialized");

{

digitalWrite(VCXO_ENABLE_PIN, HIGH);

reset();

// turn on the blue LED (GPIO2) to indicate TX

char gpio_pin_cfg_command2[] = {0x13, 0x02, 0x02, 0x03, 0x02, 0x08, 0x11, 0x00}; // Set GPIO2 HIGH; Link NIRQ to CTS; Link SDO to MISO; Max drive strength

SendCmdReceiveAnswer(8, 1, gpio_pin_cfg_command2);

start_tx();

si446x_powerlevel = 1023;

{

stop_tx();

si446x_powerlevel = 0;

// turn off the blue LED (GPIO2)

char gpio_pin_cfg_command0[] = {0x13, 0x02, 0x02, 0x02, 0x02, 0x08, 0x11, 0x00}; // Set all GPIOs LOW; Link NIRQ to CTS; Link SDO to MISO; Max drive strength

SendCmdReceiveAnswer(8, 1, gpio_pin_cfg_command0);

digitalWrite(RADIO_SDN_PIN, HIGH); // active high = shutdown

//digitalWrite(VCXO_ENABLE_PIN, LOW); //keep enabled for now

{

return si446x_powerlevel;