I think Espressif have or at least used to have their own in-house developed MAC and PHY, which is not publicly documented.<p>For the Bouffalo Lab and Beken WiFi SoCs we already have SVD files[1] for the WiFi MAC (and likely the PHY too). Thus we have nearly complete documentation for all chip registers and their bitfields. Both SoCs are based on CEVA RivieraWaves WiFi IP.<p>Also you might be able to use it as a SDR for the 2.4GHz band, there appears to be registers to send ADC data to on-chip SRAM. And USB 2.0 High Speed device functionality on some of the Bouffalo chips.<p>I was thinking of hacking it to use as a cheap uplink to the QO-100 amateur radio satellite, which uplinks in the 2.4GHz band. I think 100mW of power might be just enough for CW or some very narrowband PSK mode.<p>By the way, on the Bouffalo devices, watch out for the eFuse registers, they're not fully lockable and write protectable, one wrong register write and the <i>whole chip itself</i> can be bricked and stuck permanently in secure boot mode. It happened to me, and I'm going to try and work around it by glitching the clock input on boot, just at the right time, to disrupt the eFuse reading, just for the fun of it.<p>1. <a href="https://github.com/bouffalolab/bl_iot_sdk/blob/master/components/platform/soc/bl602/bl602_std/bl602_std/Device/Bouffalo/BL602/Peripherals/soc602_reg.svd">https://github.com/bouffalolab/bl_iot_sdk/blob/master/compon...</a>