After some preliminary testing of the first version of the circuit boards, I found that they were pretty horrible for developing on. The reason for this is the programming connections.

To program the microcontroller, I use an AVRISP MKII programmer. These programmers use an SPI protocol to talk to the chip, so it requires a VCC, GND, MOSI, MISO, SCK and RESET connections. In the initial version of the board I made these connections by soldering wires to pads on the board and then connecting crocodile clips to these wires.

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As you can see, this got a bit messy and the wires kept threatening to break off. In fact, I also, embarrassingly, forgot to leave a pad to connect to the RESET line and so I had to precariously solder this wire onto the board which kept breaking.

This wasn’t the way I wanted to continue with these boards, it was stressful and took too long to set up. So I redid the boards and had them made again. Luckily this only costs $5.50, but unfortunately it also takes about 12 days, so it isn’t something I want to keep doing, but I’ve definitely learnt a lesson.

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The new version of the boards includes 6 copper pads where I can connect crocodile clips directly. This allows me to entirely the remove the programmer when I want to and doesn’t have any of those difficult wires. It also has proper silkscreening, and I’ve managed to solder on the IR receiver!

I’ve tested it out and it works nicely. I’m very happy with it.

 

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