CW transmission using CC1101

This is covered on E2E before, see e2e.ti.com/.../157309

Here is some code that I use all the time to achieve unmodulated TX on CC1101/CC2500 series devices.

void set_tx_unmodulated_test_mode(void)

{

unsigned char reg_access;

reg_access = 0x32;
trx8BitRegAccess(RADIO_WRITE_ACCESS, PKTCTRL0, &reg_access, 1);

reg_access = 0x33;
trx8BitRegAccess(RADIO_WRITE_ACCESS, MDMCFG2, &reg_access, 1);

trxSpiCmdStrobe(RF_STX);               // Change state to TX, initiating

}

Hi 

Thanku for solution.I have one more question 

Do i need to give a randam packet to cc1101 to transmit or cc1101 will generate its own random packet ?

You could send a continuous modulated signal where CC1101 generate the data sent using a PN9 sequence (check the PKTCTRL0 register and SmartRF Studio)

Hi 

thank you now my device is transmitting continuously but I am not able to see the packets but when I kept my smart RF studio in continuous reception mode I can able to see the  change in RSSi value.But if I put my smart rf studio in packet RX mode I cant able to see the packets.is still any changes needed in firmware side.  

The original question was about CW mode. How do you send packets?
(A software example on how to do this could be found here: processors.wiki.ti.com/.../Category:Sub-1GHz)

Hi TER

I am doing in this way

I setted CC1101 register configurations after that I am giving Tx strobe command.I am not giving any data for transmission.But in my spectrum analyser I am seeing continuous packets receiving at that frequency.Is there any garbage packet transmission goes on if I din't give any data but I put my CC1101 in TX mode, Here are my register settings.

0x08, // FSCTRL1 Frequency synthesizer control.
0x00, // FSCTRL0 Frequency synthesizer control.
0x21, // FREQ2 Frequency control word, high byte.
0x65, // FREQ1 Frequency control word, middle byte.
0x6A, // FREQ0 Frequency control word, low byte.
0x6A, // MDMCFG4 Modem configuration.
0x4A, // MDMCFG3 Modem configuration.
0x30, // MDMCFG2 Modem configuration.
0x22, // MDMCFG1 Modem configuration.
0xF8, // MDMCFG0 Modem configuration.
0x00, // CHANNR Channel number.
0x47, // DEVIATN Modem deviation setting (when FSK modulation is enabled).
0xB6, // FREND1 Front end RX configuration.
0x10, // FREND0 Front end RX configuration.
0x18, // MCSM0 Main Radio Control State Machine configuration.
0x2E, // FOCCFG Frequency Offset Compensation Configuration.
0x6D, // BSCFG Bit synchronization Configuration.
0x04, // AGCCTRL2 AGC control.
0x09, // AGCCTRL1 AGC control.
0xB2, // AGCCTRL0 AGC control.
0xEA, // FSCAL3 Frequency synthesizer calibration.
0x2A, // FSCAL2 Frequency synthesizer calibration.
0x00, // FSCAL1 Frequency synthesizer calibration.
0x1F, // FSCAL0 Frequency synthesizer calibration.
0x59, // FSTEST Frequency synthesizer calibration.
0x81, // TEST2 Various test settings.
0x35, // TEST1 Various test settings.
0x09, // TEST0 Various test settings.
0x06, // IOCFG2 GDO2 output pin configuration.
0x00, // IOCFG0D GDO0 output pin configuration. Refer to SmartRF® Studio User Manual for detailed pseudo register explanation.
0x00, // PKTCTRL1 Packet automation control.
0x00, // PKTCTRL0 Packet automation control.
0x00, // ADDR Device address.
0xFF // PKTLEN Packet length.

If you don't have any data in the TX FIFO I believe that the chip will start sending preamble until there is data in the FIFO. Note that most register writes should be done in IDLE to ensure correct operation.