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Comment by mikewarot | Hacker News Reader

It's unfortunate that there's no analog (I/Q) transmission built into the TI chips. They could make fairly useful SDR transceivers otherwise.

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They demo analog (narrowband FM voice) reception in the talk. With all the uncovered control and creative digital to analog tricks, is it really not possible to transmit "analog"? I'm not sure, you might want to watch the talk.

Do you mean getting the IQ samples? On the SiLabs EFR32 chips that's possible and well documented. I've created an on-chip mono FM radio receiver, and working on getting stereo.

I'd recommend the EFR32xG23 if you would like to give it a go.

I would not be at all surprised if some "test mode" allows access to the I/Q signals. Do you have any friends at TI ?

Author here, it’s totally possible to get IQ samples from the RX chain! Unfortunately, the design of the TX chain is in such a way that it does not work off of IQ DACs, and is more limited in what the silicon can generate.

Ok... we're in agreement.... no analog TX.

That's some amazing detective work! Congratulations on pulling it off.

The “CC” in the TI part numbers stands for “ChipCon”, who TI acquired for these wireless products. The CC1100, one of their earliest parts, has a documented but unsupported debug mode which dumps raw quadrature samples out some of the I/O pins. Later parts do not mention such a feature in their documentation, but it’s not proven it was removed.

Maybe there's a misconception, but analog != IQ. Some have IQ interfaces but already digitized and you need to put in the work

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