511-bit pseudorandom test pattern

CC1125 has a build in PN9 sequence that could be used for testing. See PKT_CFG2.PKT_FORMAT and continuous Tx, random mode in SmartRF Studio.

Yes,

Random mode. Send random data using PN9 generator (Set TXLAST !=
TXFIRST before strobing STX)

What Mode to set in Receiver?

Can you give us demo code (firmware) of using this Random mode?

To send random data you have to:

PKT_CFG2 = 0x06 ; random data

PKT_CFG0 = 0x40 ; Set infinite packet length.

Write one byte to the TX FIFO before strobing STX. This is to activate the packet engine, the value of the byte does not matter.

For ETSI testing it's no requirement to set a PN9 sequence in Rx.

Vijitron, 

When you radio is fully configured, calibrated and ready to go. You run this short set of instructions and the radio will transmit modulated PN9 based data for ever.

Regards,
/TA

// use PN9 data generator
data = 0x02;              
cc120xSpiWriteReg(CC120X_PKT_CFG2, &data,1);

 // put one byte of data into FIFO to make TXFIFO!=RXFIFO
cc120xSpiWriteTxFifo(&data,1);  
trxSpiCmdStrobe(CC120X_STX);

//Halt the MCU
while(1);

Thank you for both of you!!

// use PN9 data generator
data = 0x02;              
cc120xSpiWriteReg(CC120X_PKT_CFG2, &data,1);  //Random mode

data = 0x40;              
cc120xSpiWriteReg(CC120X_PKT_CFG0, &data,1);  //Infinite packet length  added this extra

 // put one byte of data into FIFO to make TXFIFO!=RXFIFO
cc120xSpiWriteTxFifo(&data,1);  
trxSpiCmdStrobe(CC120X_STX);

//Halt the MCU
while(1);

After used this above code , i got a continous  modulated output data in spectrum .

But my receiver doesnot receive anything.

1. How can i receive this Transmitted pseduo randome bits/codes . ?

I had a look in Appln note http://www.ti.com/lit/an/swra322/swra322.pdf
  shows the hex codes. 

2. Can i see these codes?

Want to verify the data transmitting from Tx.

Moreover , i was asked to Receive and show to by my Manager that the Sequence is Random.

Please help me to get it.

This sequence does not have preamble, sync word or length information which make it a bit tricky to use the FIFO to receive. Since you are only interested in verifying the data and not performance the easiest would be to use transparent mode and just sample the output pin or looking at it on a scope to verify the data.

Hi TER

  I am not sure about the word 'Verify' which i said to you will stop me to do further. i cant see the full 511 bits in scope. Thats not an easy to do.

Before going to ETSI test , i want to test the performance of Transmitter and the Error in radio data link between Tx and Rx. For that we need to BER test.

1. Kindly please help me to test the performance by Receive the PN9 sequence (By using FIFO tricks )

2. How to do BER test , is there anything we can use by software or the inbuilt peripherals of CC1125. ?

       ( we dont have any BER test equipment and Pseduo Random bit Generator).

1) Scope with memory or a logic analyzer will do the trick. If you know the start of the sequence you may use this as sync word and use the infinite length example here: http://www.ti.com/lit/zip/swrc253

2) Check http://www.ti.com/lit/zip/swrc219

ETSI 300 220 allows you to do either a PER or a BER test.