Starting to Design the SolBoard

A project log for Solar Water Heating Controller

Hot Water with STM8 eForth

thomasThomas 10/28/2018 at 20:430 Comments

I started designing the core around STM8Sx003K3T6 (or alternatively STM8S105KxT6), and since I'd like to have a board for all kinds of "remote stuff" I decided to add an Arduino style connector, an ESP-07S/ESP12F socket, a CH340 USB/serial converter, and other goodies.  

I decided to assign GPIOs to the Arduino header so that using cheap Arduino Shields is possible (Arduino Playground's Shield Pin Usage table was very helpful). Of course, one-to-one GPIO grouping isn't possible but a bit of glue code can fix that.

While using Arduino Shield shall be possible, the SolBoard should make best use of the 10x10cm² panel size that budget PCB houses "hand out" to the masses. I hope to find the right mixture of features and pragmatism so that my solar controller board can also be used as a prototype board or for other logging or control use cases.

The general layout of the board is this:

There are now some things to decide:

I would be happy to receive some advice from the community!