Liz McCormick


Week 06 - Embedded Programming


Project 02b

This weeks assignment was to program our boards to do something, with as many different programming languages and programming environments as possible. Feeling a little intimidated by this task, I definitely took the easy road for this assignment.

Building the Board


Project 02a
A few weeks ago I built Neil's "hello world" temperature board, and I only just this week realized that I used the wrong temperature sensor. I used the blue sensor from the drawer "temp. chip".
Project 02c
Not surprisingly, the program didn't really work.
Project 02b
I found the drawer for the "Thermistor 10K ohm". It's green like the one in Neil's photo. I tried to delicately remove the blue one from the board and unfortunately I ripped teh copper spots up from where it was sitting. What started out as a simple 5 minute project turned into a 90 minute project as I had to remake the board and resolder all the parts.



Project 02b
I had already programmed my programmer a few weeks ago so I was able to skip this step.
Step One: Plug the programmer into the computer with a mini USB cable.
Step Two: Plug the temperature board into the programmer using the ribbon cable. ORIENTATION MATTERS. I spent quite a while trying to program by board with the plug facing the wrong direction. This is a dumb mistake that can be easily avoided. The image at the top of the page shows what it SHOULD look like.
Step Three: once you've programmed your board, you can plug in the serial cable into the board and back into your computer.
Project 02c
And here it is with the python program running.
However, it doesn't seem to be taking the same measurements as my storebought temp/humidty measuring device. (The Device reads 26.2% RH and 24.7C, so my python script is off by 3.5C). This means that I'll need to spend a bit of time calibrating the program.

Commands in Terminal
Navigate to the folder: $ cd ~/Desktop/files
Program the board: $ sudo make -f hello.temp.45.make program-usbtiny
Identify your serial cable: $ ls /dev/tty.usb*
Run the python script: $ python /dev/tty.usbserial-A904NKJC
Project 02c