Sverre,
I tried your proposed configuration settings without positive results. Your proposed configuration (the important registers) was the following:
PKTCTRL0 = 0x00 // CRC_DISABLED + FIXED_LENGTH
MDMCFG2 = 0x31 // 15/16 SYNC WORD
MDMCFG1 = 0x02 // 2 PREAMBLE BYTE
MDMCFG0 = 0xF8 // DIFFERENT CHANNEL SPACING
MCSM0 = 0x18 // CALIBRATE IDLE->RX
I changed to 433 MHz maintaining the data rate. I also changed the configuration because I need CRC and variable packet length. In addition I adjusted the sync word and preamble length. The remaining settings were left unchanged or as default upon chip reset.
PKTCTRL0 = 0x05 // CRC_ENABLED + VARIABLE_LENGTH
MDMCFG2 = 0x33 // 30/32 SYNC WORD
MDMCFG1 = 0x22 // 4 PREAMBLE BYTE
MDMCFG0 = 0x10 // DIFFERENT CHANNEL SPACING
MCSM0 = 0x38 // CALIBRATE 4th TIME TX/RX->IDLE
With such changes I am unable to receive anything at all. The devices are close to each other but there is a 30dB attenuator in one of them to ensure that the AGC does not saturate. I've also checked with a spectrum analyzer and there is power coming out of the antenna, so that is not the problem. I also tried to reduce the sync word and preamble length to your proposed settings without observing any difference.
As you can imagine, I am at complete loss. The CC430/CC1101 should be able to go up to 250 kbps with OOK/ASK but I cannot be able to get it working. Can you suggest other aspects to check or put me in contact with a FAE?
Thanks in advance!
Regards,
Pere