I recently started coding on a raspberry pi. I build a circuit with three buttons, an LED and a 7 digit LCD. Its a fairly simply thing. You can set a time value with the + and - button in seconds and then press the other one to start a countdown. I use this to do triggered long exposures with my camera. However the raspberry pi is to big and bulky and needs to much energy.
Then I put my code and my circuit on an Arduino UNO which is an improvement in size and energy consumption.
Because my program is very simple I am sure that there must be a way to get this on a much smaller chip. I need some kind of programmable chip where I can put my code onto. Something that is small and dont has any other fancy features or more calculating power than I could need. As far as my knowledge goes I dont have any idea how to get into that.
At work we have a 3D printer with a W1209 temperature relay controller on it. This is a small circuit with the same 7 digit LCD pane and the temperature is also settable with two buttons. This inspired me to look for something much more primitive that would be enough for my needs.
Can you recommend any hardware or some tutorials about that?