The assignment this week was to add a device to a microcontroller board and make it do something. I decided to add an array of Charlieplexed LEDs. I started by downloading the traces and interior files, C code and Makefile from this week's page. Next, I milled the board, stuffed, and programmed it without much of a problem. This part of the process is starting to get more familiar and routine the more I do it.

Wanting to take the assignment a step further, I worked with my colleague Lumumba Seegars to identify which pins were needed to control each light. By identifying the needed state for high, low, and off we could plot each light like a grid and turn the lights on and off in any sequence we wanted. Working together we also created new led_cycle()'s from the code to give a sequence looking like letters of the alphabet.

Revised file used for programming - C Code

I re-wrote a really long program which was too large to fit on the microcontroller. I knew this because while trying to program thge board I got an error message and I saw that the memory needed was 145% of what was available on the microcontroller. So, I programmed the board with two separate versions of an alphabet sequence. One video has a scrolling message that says 'A B C ' s' and then starts into the alphabet flashing each letter. Next is a second video of the entire alphabet sequence. The letters are not perfectly sized but you can see them clearly.

Video

Another video

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