## cst816s 

A rust no_std driver for the
Hynan / Hynitron CST816S touchpad device. 
This driver was originally developed for the PineTime smart watch.

## Status
This is work-in-progress
- [x] Blocking mode read of available touch events
- [x] Reading slides and long press gestures
- [ ] Reading click and double-click gestures
- [ ] Interrupt handling of touch events
- [x] Debug build
- [x] Release build
- [x] Debug build of touchpad example runs on PineTime
- [x] Release build of touchpad example runs on PineTime
- [ ] CI
- [ ] Documentation

## Examples

The following example was developed for and tested on the 
[PineTime](https://wiki.pine64.org/index.php/PineTime)
nrf52-based smart watch.

Note that you will need to 
[clear the nrf52 flash protection](https://gist.github.com/tstellanova/8c8509ae3dd4f58697c3b487dc3393b2)
before you will be able to program the PineTime. 

For installation and debugging you can connect with the PineTime on its SWD debug port using, for example:
- openocd (built with proper support). We've used an inexpensive ST-Link adapter to with openocd. 
- [daily build of the Black Magic Probe firmware](https://github.com/blacksphere/blackmagic/wiki/Upgrading-Firmware)
- Segger J-Link or similar

When you're ready to install on the PineTime, you can run the example with:

```
cargo run --example touchpad
```

## Resources
- [Datasheet](./CST816S_V1.1.en.pdf)
- [Reference Driver](https://github.com/tstellanova/hynitron_i2c_cst0xxse) in C, from Hynitron. 

## License

BSD-3-Clause, see `LICENSE` file.