The aim for this week was to:
1. Make the Fab (tiny) ISP in-circuit programmer.
I chose the resonator design.
I cut two boards. The first went well, after I worked through all of the software procedures. Our machine is using the older version of fabmodules. Here is a good PDF, that features the earlyer Fab Modules version being aplayed to the MDX 40.
Apart from being shown how to use the machine by my Fablab people, I made good use of the 2015 Fab Academy archives to help me through. The best Youtube tutorial on soldering technique I found was This 1980s job
The second board didn't cut so nicely. It cut one half shallow and didn't cut the other at all. This turned out to be a good opportunity to practice and gain confidence operating the machine. I discovered the reason it didn't cut all the board evenly was because I hadn't paid enough attention to double-sided tape on the back of it.
I started my soldering at the usb end, and quickly had to do some desoldering. I only remembered to check the polarity of my diodes, after I had soldered them on. I had to desolder one of them, then replace it. I used the copper braid, which eventually did the job. I am going to try using a desolder suction pump in future.
Actually, it nearly works... everything appears to work but neither the Mac or the Ubunto machines recognise it. I need to do some trouble shooting.
I made another board. It passed all the initial tests without fault. I plugged it all into the AVR and got the green light. I went through the programming procedure with everthing normal until I came to a discrepancy between what the tutorial said I should see and what I got. The value of these: text, data, bss, dec and hex filenames are different to the outcomes I should have got. My values are text 0, data 2002, dec 2002 and the hex filename is 7d2 main.hex.
The other difference is I had the error message: unable to read hfuse properly.Programmer may not be reliable.
I ran through the programming process again. This time I didn't get the error message, but the different values relating to the hex filename remained, and again, the Fabisp was not recognised by my computer or the Fablab Ubinto system. Yet as before, other known to function isb is recognised by my computer.