Week 4
Electronics Production
The fourth assignment for this course was to produce an in-system programming circuit (ISP) using a mini-mill and surface mount electronics. I have been soldering for years, but basically always in through-hole arrangements. This experience actually proved detrimental and I struggle a lot with transitioning to surface mount, but was eventually successful.
Initial Milling
I thought Valentin Heun's Design was quite elegant and a good starting point for the ISP. Unfortunately, my hold down technique for the first cut was not strong enough and I ended up breaking one of the outer traces when the board came loose. I thought I could short it manually with a small wire, but this board wouldn't show up when I tried to program it.
I tried Valentin's board again, but kept getting errors when I got to the "make fuse" and "make program" part of the programming. I tried debugging a bit, but nothing worked and I have to assume there was a problem with my wiring.
Try 2 (I manually cut the outer trace to see if it would show up using lsusb....it didn't)
Next, I figured something was off with my setup so I just went back to the gold standard, the original HelloISP44 board. My first attempt worked when I did the initial programming, but when I desoldered the 0ohm resistors, I accidentally broke the traces and the board was bricked (even after a shoddy repair)!
Try 3
Finally, I tried one last time and made some actually nice solder joints, got the board programmed and verified it was working!
Try 4! It worked!
My text dump from the command line programming is attached at this link
It even shows up in a device list!
All in all, this was a fairly frustrating week but I definitely got quite a bit better at detailed soldering and it was a great relief when the board finally worked!