This week's lab was an introduciton to circuitry and board stuffing, with an emphasis on using the Rolland mill for cutting traces, and soldering.
I had some soldering experience from previous projects, but had never used a mini mill like the Roland before, so was excited to learn how it worked.
fabmodules.org was used as the CAD/CAM tool for running the mill. it was extremely simple to import a PNG (shown below) and generate toolpaths for the various bit sizes. With this done, it was a matter of zeroing (again an intuitive process) and hitting print.
I cut two boards (in case I made an inevitible error) in the format which included the 2pf capcacitor in the crystal. This was done to reduce the number of components to keep track of between cutting the board and finishing soldering. I have included a full component list for future references:(1) mini usb connector (1) 1k resistor (1) 499 resistor (2) 100 resistor (1) 10k resistor (1) 1uf capacitor (1) 20mhz crystal with 2pf capacitor (2) jumpers (1) attiny 44a controller (1) 2x3p header (2) 3.3V zenner diode
The first board came together rather quickly until I noticed to my chagrin that I'd installed the attiny upside-down.
I started over.
The second board came toeger rather quickly, and I started work on the programming process on my laptop which was running Xubuntu 14.4. The first two commands:
Went through as expected. The next command:
sudo make fuse
Didn't, and reported the following error.
avrdude -c avrisp2 -P usb -p attiny44 -U hfuse:w:0xDF:m -U lfuse:w:0xFF:mavrdude: usbdev_open(): did not find any USB device "usb"
make: *** [fuse] Error 1
I used a voltmeter to check resistance across all components, looking for shorts and cold joins. Fortunatley all connections were opperating as expected, though it meant that I was still at a loss for where the issue was coming from.
I emailed the architecture session and eventually received a response suggesting that the issue I was having may stem from a "toolchain error", which means that the stuff to install the stuff was not installed. The recommended fix was using the computer available in the RPL to complete the programming.
Sure enough, the program pushed through on the first try, and now appears to be opperating as intended. Very fun project.
Web design deteriorated though...