Explorable: Changing Apollo3 <> SX1262 SPI Frequency?

Wireless & IoT LoRa (Long Range)
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I know it may seem like an odd request, but I’d like to lower the SPI communication bitrate on the Apollo3 to SX1262 SPI port on the ExpLoRable board. The reason has to do with limitations of equipment that I’m using to look at the data going over this interface. I have successfully probed it, but now I need to slow it down a little.

I do not see a way to do this, and moreover I do not see where it is being set at all.

Thanks for your help.

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I think you’d need to edit the bootloader https://github.com/sparkfun/SparkFun_Lo … Bootloader with alterations gleaned from the apollo3 datasheet (starts at pg 216 or so) https://cdn.sparkfun.com/assets/6/3/9/3 … v0_9_1.pdf and the SX1262 datasheet https://cdn.sparkfun.com/assets/6/b/5/1 … asheet.pdf (pg 50, et al)

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Thank you for this information.

I do not see source code for the bootloader, only a binary. Since SPI is a synchronous connection, SX1262 datasheet is not required at all for the change I’d like to see, which is to simply slow the SPI clock.

Could someone perhaps explain why calls to MbedSPI::beginTransaction() including settings for frequency do not appear to be honored? My thoughts were that if RadioLib does not alter SPI frequency, perhaps I could set it using the settings structure with the beginTransaction() call and it’d be retained during the RadioLib calls, but it is not.