PCB Fab

The purpose of this week was to learn how to:

1. Run the software needed to mill copper traces on the PCB.

2. Figure out what components needed to go on the PCB and solder them on.

3. Figure out what wires were needed to program the PCB and make them.

4. Program the PCB.

I ended up making two PCBs this week. The first one I made on Ilan and Max's mini milling machine. I used Ilan's computer to run it, since the operating system on my Mac is too old. It worked well except that it seemed to have missed a couple of contours and so did not mill out everything that needed to be milled. I was able to scrape off the rest and soldered on the components (easier than I expected). But, unfortunately I hit one of the components thereby breaking it off, taking the copper traces with it.

I made the second one on the Modela (thank you to Erik for setting me up on it). This one also didn't cut quite right and left rough traces that I tried to clean up with by lightly scraping them with my fingernails. I'm still trying to understand all of the necessary command lines needed to open CadPy and why it works sometimes, but not others. That's going to take a while.

Soldering the second one went well and then I was off to programming it. I was not expecting the programming to go very well considering my utter lack of experience and the way the project had gone so far this week. Upon first try at programming I immediately got: "AVR not responding".

These were my steps to program the board:

1. Plug in cables to board in correct orientation (top right pin is 1)

2. Plug in cables to computer.

3. Open terminal window and use command: python term.py /dev/ttyUSB0 9600-- this powers up the board

4. Open a new terminal window and use command: avrdude -p t45 -c bsd -U flash:w:hello.serial.45.hex-- this programs the microcontroller chip

* This is where my adventure ended in the "AVR not responding" error

* I tried a variety of remedies hoping the cables were the problem, but eventually concluded that it was the chip. After having already made two boards, my patience had run out for the week. I hope to try again next week.

This is a screen shot of all the programs I installed on my PC to complete this project.