I must get rid of the ESP8266!

I took my balancing robot into the office today, plugged a USB wifi dongle into my computer. I connected to the ESP8266 in AP mode. Sadly, it didn't work so well: the connection dropped regularly, about one in 3 packets got dropped, and the buffer overrun problem I previously thought only applied to TCP packets started happening to UDP: the tails of previous packets getting included at the end of new ones.

OK - so I've eliminated Bluetooth completely because Linux is too crap at it. I've pretty much ruled out WiFi as too expensive, or too poorly implemented on the embedded side. What's left?

Well, I have two CC2500 modules. On the embedded side, the SPI interface is fairly (very?) convenient. On a PC or a phone, not so much, although I could stick one in a box with a micro controller to get something usable for a pc.

There's also the nRF24L01+ which there are also cheap USB adapters for. The breakout boards seem to be available for £1, so it's probably worth ordering some. They aren't breadboard friendly though: they have a 2 row header.

Anyway, I have a pair of CC2500s. I also have a Nucleo-411RE, and according to this, USART2 is available as a virtual serial port via the ST-Link USB port. That's extremely convenient. I can do SLIP over the serial port.

The datasheet for the cc2500.

It's rather daunting: there are a lot of settings to choose from. I'm going to assume this Arduino library chooses some sensible defaults. Besides, I might want to be compatible with it.

Perhaps I'll just start with the Arduino library so I can see if the modules work. To be continued...

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