Help (a noob) with configuring  CC1101 Sub-1GHz RF Transceiver module - Page 1
Forum section: electronics / beginners

author: Dundarave
author_rank: Regular Contributor
timestamp: February 04, 2019, 06:20:43 am
content: I've been working on a little remote control windowblind project, trying to use a cheap little $3 433MHz regenerative receiver, but the output from it makes it difficult to detect the transmitted data reliably with either a Picaxe or an RPi. So I thought I'd throw some money at the problem, and got a CC1101 transceiver module for all of $6, lol. Given that it has a wide range superhet transceiver, and a 94-page data sheet to boot, I figured that puppy ought to serve the 433 MHz transmitted data up on a platter, decoded, and in 6 different languages.The problem, of course, is that something that complex is a bear to configure correctly unless you have a clue, which I do not.I found some Github code (https://github.com/SpaceTeddy/CC1101) that has some very nice demo TX & RX programs which will configure and set up the module, which I successfully compiled and ran on my RPi. The crux of the problem is this: the RX code is asking for, among other things (such as the modulation and the freq range, both of which I know), the "channel number" and "my address", which I'm thinking is either the SPI address or an arbitrary radio receiver address(?).In either case, I don't know what to possibly select. That fact that it needs two unfamiliar parameters makes me think that I'm way out of my league with this module: I tried a few different settings, put a scope on the SPI lines, and transmitted away looking for any sign that it might be receiving something, but without success.I'm just trying to get a clean demodulated 433MHz square wave pulse sequence output from my window blind remote control transmitter so that I can recognize the specific encoded transmission, and then use the RPi to do something about it.Does anyone with any familiarity with the CC1101 know what the minimum config parameters would be to do simple on-off keying modulation detection of a plain-vanilla 433MHz remote control signal? Or better yet, have some code that they would share to enable the CC1101 for that purpose?Thanks for any assistance. -

author: n3rdx
author_rank: Contributor
timestamp: February 05, 2019, 07:31:27 pm
content: I think this topic could get more answers in the microcontroller forumhttps://www.eevblog.com/forum/microcontrollers/- it's not really a beginner level question, IMHO. See you there.

author: n3rdx
author_rank: Contributor
timestamp: February 05, 2019, 07:37:14 pm
content: Quote from: Dundarave on February 04, 2019, 06:20:43 amHow much of Figure 10, Figure 11 ofCC1101 application notehave you implemented? Did you set up a test environment using their tools as outlined in the note?

author: Dundarave
author_rank: Regular Contributor
timestamp: February 11, 2019, 12:53:43 am
content: Just to close the loop on this post: I ended up rolling up my sleeves and decided to become an expert on the CC1101. All I actually ended up with was rolled-up sleeves, but I did gain an appreciation for how complex and complete CC1101 is for sophisticated and robust sub-GHz communications.Unfortunately, with respect to my particular needs, the CC1101 really just wants to deal with structured data packets, the kind with 2-byte preambles, sync words, and packet length fields. It only marginally tolerates mongrel 433MHz signals of the sort that I'm dealing with: those that come from cheap, primitive protocol 433 & 315 MHz transmitter & receivers. For all its sophistication, the CC1101 essentially tells you that if you aren't going to be receiving well-formed data packets with preambles and sync words, then you'll have to use the tradesmen's entrance, where it simply passes out the same dodgy output as the cheap regenerative receivers, but only after you've cracked the configuration code for the 47+ configuration registers. Trust me, it wasn't worth it.Long story short: the cheap 433 MHz receiver I started with actually did a better job demodulating my rough-and-ready 433MHz signal than the CC1101, so I've focused on step-wise improvements on cleaning up the demodulation from it. One improvement, for example, was the use of a solid power supply (my new Siglent 3303X-E!)... that seemed to go a long way to cleaning up some issues I was having.Anyway, there it is for others who, in the fullness of time, come across this thread looking for 433MHz and/or CC1101 keywords: know that unless you're dealing with 433MHz remotes which are using protocols that the CC1101 likes to deal with (i.e. those with preambles and sync words), you should probably stick with using the simple, discrete component regenerative 433MHz receivers for a few dollars on Amazon. But that said, when it comes to designing any new sub-GHz radio data transmission applications, the CC1101 is certainly going to be my go-to device, especially now that I've invested the time to understand its capabilities.