- Jorge’s Status Report for 3/18/22
This week we tested the software and made sure it worked well enough with a prototype of the board. We put in an order for the Diode’s we will need and with those we will know finally whether absolutely everything is working as intended. But as mentioned in the group report, the behavior is about what we expected. (The software works fine but once we do inputs from separate columns ghosting becomes an issue.)
Besides that it was my time to start work on the PCB layout. We ran into a slight delay which I made up by working on the layout on Friday. The Eagle license we had was only the free one and our Board dimensions were beyond the allowed limit. I had to submit some enrollment documentation, transcripts, and an ID but we ended up getting the Eagle education (through Fusion 360) license approved the next day.
Here below is the PCB:
Notes about the board:
- It has no ground plane, this is unnecessary because we would only need a ground plane for the LEDs in the switches, which we are not using
- I am slightly worried about the space the Diodes (not the LEDs) take up, but if they take up space for our switches we can just solder them on the back of the board so I don’t see that as being a big problem.
- The pin headers that interface the Pi are organized as rows and columns, it keeps the board neat and orderly. Rows flow through the bottom of the board, columns through the top. Both eventually rout to the top to their respective Pi interfaces
- LED pins are left disconnected for now, if we decide to use them for some reason I can add some wires and resistors to make use of them, but it isn’t high priority.
- Spacing is made with 20mm keycaps in mind, and a key-guard. Hopefully the dimensions wont be too ridiculous but there is room to make changes next week before we order the board.
My main worry right now is the time frame, we may need to pay for express shipping so we can get the board on schedule.