The first couple of board batches have been primarily human-machine interface (HMI) and interconnect components.
The HMI component collection so far includes:
- 5mm LED
- 5mm bicolour LED
- button
- LED/button
- pot
- multi-position switch (4 positions)
- toggle switch
- rotary encoder
All of these components can be panel mounted. The boards convert the pin connections into a Grove or 2 pin JST PH connector. In some cases resistance is added eg for LEDs. The boards are extremely simple, and the layout time was minimal. The boards are small, so the cost is low when buying in volume.
The composite HMI is wired with PH and Grove cables, which can optionally be consolidated into byte-wide breakouts. Then a 10-wire Dupont cable is used to carry signals back to the MCU. This connector works well for prototyping, but I want to find one (probably a JST PH) that will be better for use in the field.
I use #4-40 standoffs and screws for holding things together mechanically. M3 works just as well. I chose #4-40 over M3 because we have a local supplier that stocks these and they are cheap.
While this concept may use more parts, it all comes apart and there is very little waste. The only part that cannot be easily reused on this first demo HMI is the acrylic panel.
There is a lot of detail, on various topics, that I think is best covered one subject at a time, in the log.