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Hi

Here is some code you can use to test the  RFTXRXIF flag. This code can be tested together with SmartRF Studio as the transmitter (use the recommended 1.2 kBaud setting).

void main(void) {
  // Choose the crystal oscillator as the system clock and set system clock
  // speed = fRef (fxosc)
  CLKCON = CLKCON_26_MHZ_XOSC; // Request switch to crystal oscillator
  while (CLKCON & OSC_BIT); // Wait until the clock switch has occurred
  SLEEP |= OSC_PD_BIT; // Power down unused oscillator

  PKTCTRL0  = 0x05; // packet automation control
  FSCTRL1   = 0x06; // frequency synthesizer control
  FREQ2     = 0x21; // frequency control word, high byte
  FREQ1     = 0x65; // frequency control word, middle byte
  FREQ0     = 0x6A; // frequency control word, low byte
  MDMCFG4   = 0xF5; // modem configuration
  MDMCFG3   = 0x83; // modem configuration
  MDMCFG2   = 0x13; // modem configuration
  DEVIATN   = 0x15; // modem deviation setting
  MCSM0     = 0x18; // main radio control state machine configuration
  FOCCFG    = 0x17; // frequency offset compensation configuration
  FSCAL3    = 0xE9; // frequency synthesizer calibration
  FSCAL2    = 0x2A; // frequency synthesizer calibration
  FSCAL1    = 0x00; // frequency synthesizer calibration
  FSCAL0    = 0x1F; // frequency synthesizer calibration
  TEST1     = 0x31; // various test settings
  TEST0     = 0x09; // various test settings
  PA_TABLE0 = 0x50; // pa power setting 0
  IOCFG0    = 0x06; // radio test signal configuration (p1_5)

  // Infinite loop
  while (TRUE) {
    UINT8 i = 0;
    RFST = STROBE_RX;
    
    while (!RFTXRXIF);
    RFTXRXIF = 0;
    rxBuffer[i++] = RFD;
    
    while (i < rxBuffer[0] + 3 ) {
      while (!RFTXRXIF);
      RFTXRXIF = 0;
      rxBuffer[i++] = RFD;
    }
    if (rxBuffer[rxBuffer[0] + 2] & 0x80)
      packetReceived++;
  }
}

I have tested this and it works. If you get this to work your problem is probably related to the way you set up your interrupts.

BR

Siri

Hi Siri

Many thanks for your reply.

After checking all the regsiters in your sample against my code I find the only differences that have an effect are to do with the packet size. I have PKTCTRL0 as 0x04, i.e. fixed packet size.

I have now tried a variable size and find that all data is received as expected, as long as PKTLEN is defined as longer than the actual packet size transmitted. That's fine and as expected.

If I try a fixed packet size on the transmitter, I seem to get one good packet received but no more; subsequently I just get  one byte and no further RFTXRXIF assertions (whatever the packet size is defined as).

I am trying to receive packets from an older CC1010 system and I don't know what the packet size is going to be before I receive part of it. The size is not defined in the first byte after SYNC, as it would be for a CC1110 packet (the size is actually in the 3rd byte, the first byte is the destination address of the packet).

Is it the case that, even when receiving data in a 'byte-by-byte' mode (i.e. not using DMA for packets) , that the receiver will still attempt to collect 'x' bytes before  RFTXRXIF is asserted, where x is either the first byte of the packet (variable length mode) or the number of bytes defined by PKTLEN (fixed length mode)?  In other words, is there any way I can set this up to receive (and interrogate) just three bytes of a packet, without knowing the packet size or waiting for an arbitrarily long packet to arrive?

If not, this gives me a problem because I need to send an acknowledgement within a short time of receiving the packet. If the packet is small then the originator of the packet will time out waiting for this acknowledgement. (The orginator of the packet is using the 'SImple Packet Protocol' which was example code for the CC1010.)

Best regards

Chris

Hi

Assume you want to receive the following packet:

Preamble - sync - x - x - Length n - data_1 - data_2 - ... - data_n-1 - data_n - CRC - CRC

On the receiver you should use fixed packet length and set packet length to a high number. Then you can run the following code:

while (TRUE) {

    UINT8 i = 0;
    RFST = STROBE_RX;
    while (i < 3 ) {
      while (!RFTXRXIF);
      RFTXRXIF = 0;
      rxBuffer[i++] = RFD;
    }
    PKTLEN = rxBuffer[2] + 3;
    while (i < rxBuffer[2] + 5 ) {
      while (!RFTXRXIF);
      RFTXRXIF = 0;
      rxBuffer[i++] = RFD;
    }
    if (rxBuffer[rxBuffer[2] + 4] & 0x80)
      packetReceived++;

}

It is here assumed that CRC calculation is enabled together with append status.

BR

Siri