I need to get up to date on my project and flesh out the details and make a plan.

I went through my old project folder on my computer and I was surprised at the lack of things written down. There was only a simple text file with a little bit of information. So I made a new project folder and a treesheet document to manage this project instead of a text file.

This project can be divided into several sub-projects. Which of each have to divided further. There will be various skills to learn for each which is fun. For example like this.

• Codec Breakout PCB
• LTE Modem
• Pico
• Power supply
• H-Bridge
• Keypad matrix scanner
• Connecting everything together

Since I moved to Japan there is also a lack of equipment that have to be adressed at some point.

The brain of the project will be a Pimeroni Pico LiPo board. Going through the datasheets for everything I discovered that I need more GPIO than I thought. That is why I will get access to 7 more pins by offloading the keypad matrix scanning to a different device, the SLG46826 (an opportunity to learn something new) which sends it through I2C.

For modem communcation I need to level-shift all signals since the modem is at 1.8 volts and the pico is at 3.3 volts.

The 40volt PSU and H-bridge design have to be revised. 

Next I have to go through all the parts I have.