We are redesigning next gen product but must still communicate with existing product . We wanted to use the CC430 but uncovered the following issue. The earlier design radio is configured to have two different 16 bit Sync words for total 32 bit Byte Sync. We can not change this firmware. It looks like the CC430 can do 32-bit sync but repeats one 16-bit Sync word. This prevents existing product from communicating with the CC430 based design. Is there anyway to provide two unique 16-bit words ?
CC430- Byte Synchronization
Byte synchronization is achieved by a continuous sync word search. The sync word is a 16-bit configurable field (can be repeated to get a 32-bit field) that is automatically inserted at the start of the packet by the modulator in transmit mode. The demodulator uses this field to find the byte boundaries in the stream of bits. The sync word also functions as a system identifier, because only packets with the correct predefined sync word are received if the sync word detection in RX is enabled in register MDMCFG2.
Hi,
You are correct in your assumption that the CC430 can only use 16 bit sync word, but the sync word can be repeated twice to form a 32 bit sync word.
One suggestion is that you use the 16 Least Significant bits on your "old system" 32 bit sync word as sync word in the CC430. That way the CC430 will listen for the last part of the old sync word.
If you also need to send data to the old system from a CC430 you can use the 16 Most Significant bits from the 32 bits sync word as sync word and then send the 16 Least Significant bits of the sync word as payload. This will require that you use fixed packet length on the CC430.
-Jonas
btw, the cc1101 and cc430 handles the sync word in exactly the same way. The title of your post indicates a difference in the way sync word is handles between CC430 and CC1101, this is wrong.