I’m a bit late in reporting on this, because much of the work happened over the Labour Day weekend, waiting in ferry lineups and such. I spent too much time poring over datasheets, double- and triple-checking my design, and while I’m still not sure that it’ll work, I’m going ahead with the first revision of my first Raspberry Pi HAT.
My first HAT is intended to be a part of the Office Robot. But I can see some other potential uses for it, so I tried to make the design a little more flexible.
- Mono microphone input
- 3.7W stereo speaker output
- SPI peripheral connector, with an interrupt and reset line
- I2C peripheral connector, with shared interrupt and reset lines
- 5V power input
- Power control button
I am confident that the level-shifted peripheral connectors will work properly, as I’ve prototyped both on a breadboard. It’s the audio stuff I’ve never played with before, that I’m nervous about. But even if those bits don’t work properly, the HAT will still be a lot cleaner than the breadboard covered in jumper wires.
I’ve got my fingers crossed, but if I have to build Version 2, I’m okay with that, too.