« Back to home

PiStation Updates

Despite a very hectic weekend where I didn't get a lot of time to spend on the project I've managed to make some progress on the PiStation.

First up was testing the button circuit and making sure I could read the button state from the GPIO (oh, and making sure I didn't let the smoke out of the Pi with the circuit either). I put the circuit together using a set of breadboard cables I got from Adafruit. Not as neat as I normally like but certainly quick and easy to do.

To test it I wrote a simple Python program using the RPi.GPIO library. All it does is periodically poll the status of the IO pins the buttons are connected to and display them on screen.

Everything worked as planned so I put the circuit onto a bit of strip board ready for mounting in the final assembly. There is a bit more work to do on some software to make it easy to integrate but the hardware works as designed so I'm happy with that.

While I had a hot soldering iron I decided to modify the power board with the changes I had planned earlier. Although my original idea was to use two 22 Ohm resistors to help distribute the heat across a number of components there was no way I could modify my existing board to fit both of them in so I wound up using a single 10 Ohm, 5W wire wound resistor.

Space is still at a premium but I managed to modify the original board to incorporate the new changes. As you can see in the image I had to mount the resistor vertically to fit it in, this is probably beneficial as the heat it generates won't be transferred to the PCB and there is plenty of airflow around it.

I also took the opportunity to add a heatsink to the regulator chip itself so that should help cool it down as well. I haven't had the chance to test this over any length of time, all I've been able to do so far is power it up and ensure that I still get the required 5V output from the circuit.

The next step is to revisit the layout of the front panel and the enclosure. Now I have the actual working boards that need to be fitted in to it (and after seeing how my original design worked in reality) I can come up with something a little bit better. The general shape will remain the same but the size of the front panel and the way I layout the PCBs in the rest of the enclosure are going to go through a bit of a revision.

That's a job for tomorrow night though.