Using Clear Channel Assessment / CSMA in CC1120
You may have come across other replies to your questions but if not, here's some answers that may interest you.
The CC112X is a sub-1GHz radio transceiver and if you're looking at doing WiFi or in any case, around that frequency, I can tell you it won't be possible with the CC112X. You'll need to look specifically for transceivers that are specified to operate at those frequencies etc. Ti, or other vendors may propose these.
The CCA/CSMA and or LBT (Listen Before Talk) may be of interest to radios for which particular standards requires them to follow a particular protocol to ensure they conform to the legal requirements for certification.
One such standard that covers the Europe (or more so EMENA) zones, is the En 300-220 for instance, or the En 300-328. There is a description of the procedures/work-flow to follow for implementation of CCA, LBT etc. but in a nut-shell they are generally fairly easy to implement if you already master the radio transceiver's basic registers, for transmitting/receiving, the reading of the Tx and Rx FIFOs, reading of the RSSI and decoding of the packed adressees, sync-words, and CRC etc.
For instance it may require a transmitter Tx, first to monitor the channel prior to transmitting anything, this could be done by reading the value of the RSSI registers to ensure a certain receiver signal threshold is not exceeded in Rx mode (which may suggest there is another transmitter on that channel already transmitting), then to hold back some fixed minimum delay, prior to commencing transmitting, and to keep doing so whenever ready to transmit. If the channel is busy, there may be an option to hold back for a random period, prior to re-try etc. Its all about &quot;polite spectrum access&quot; and it is a requirement for may radios that are subjet to particular standards some of which where mentioned above.
There are some particular registers you may use to help you with implementing what you require, but this does not mean your radio will conform to the particular standard it is being covered by. I would suggest rather you take the standards that cover your radio frequency(ies), then look at what they want you to implement when it comes to &quot;polite spectrum access&quot; if it is required, then use the CC112X's basic register access for Tx transmit, Rx receive, FIFO access, RSSI reads etc. and the various settup registers required which you will need to do regardless of the particular registers for so called CCA/CSMA, LBT etc. cause you should be able to do this with the basic CC112X registers, and some delay loops and/or microprocessor interrupts etc. The carrier sense register may do this automatically, but it assumes you already use a particular sync word programmed, and the RSSI threshold is also programmed etc. There are interrupt GPIOs that are raised to alert you, so you may need to also read these GPIOs, so you see there's a bit of setting up before all this automatic CCA/CSMA/LBT is implemented for you. Might as well do it yourself by polling the RSSI registers etc. decoding the sync-words, and the frame-packet addresses etc. as it'll be more flexible in the end ..
Hope this helps in some way, otherwise you may want to contact the vendor of this CC112X transceiver as they'll be more than happy I'm sure to point you in a more particular direction...