USB host shield on Espruino: Part 4

Today there won't be any new code, as I'm still trying to get it to work. After yesterday's successes in reading the device and configuration descriptors, I decided to implement a USB driver for the TUSB3410 chip from Texas Instruments (TI) on top of the USB stack I've written so far.

During my previous Tidepool hack week last year I wrote a WebUSB driver for the TI chip. This chip is used in the USB cables that communicate with the Abbott FreeStyle series of blood glucose meters, and there is no macOS USB driver available. Using WebUSB, I was able to successfully download data from a meter on macOS. Now I would like to see if I can get data from the meter using the Espruino and the USB host controller chip.

I'm writing the the USB stack for the controller chip so that it looks like the WebUSB interface. Therefore it should be pretty easy to re-use that driver code, as long as the USB stack underneath behaves the same as WebUSB.

While working on this today, I realised there are still a number of functions I need to implement in my USB stack, like control transfers that send data. When I get this to work and retrieve data from the meter successfully, I will put the code on GitHub and see if I can write an explainer here.

#Electronics #Tidepool