Input Devices

measure something

The goal for this week: Measure Something

The Plan: To make a bunch of handprint shaped pads that read the pressure applied by your hand.

The Reality: Get one pad to let you know if you're touching it and how much.

Vinyl Cutter

I learned how to use the vinyl cutter to make circuits (Thanks Emily M.) and used it to make Neil's step ressponse circuit.
I also made a circuit board with the Roland Modela. There were no FTDI connectors left in the lab, so I used some similar-looking right-angled connectors. Mistake #1
The length of the pins wasn't deep enough, so in the end I soldered FTDI pins onto the right-angled pins.
MISTAKE #2:
I tried to attach both the ribbon cables at once. Which caused the first casualty; My milled circuit board.
Fortunately I still had my

Coding

I didn't find many tutorials that helped out with the very very basics. Thanks to Sam and Dan, I am piecing the different parts together which I will compile into a comprehensive tutorial. For the moment, the steps that I followed were:
1. Open terminal
2. Download the .c, .make and .py files into one folder on your computer. Save the .make file as Makefile (the capital M is important)
3. Prerequesite for compiling the make file is having crosspack and xcode on your computer.
4. Enter the folder you've created with the relevant files
5. Enter the command $make
5.5 Enter python 6. The computer should take the source code (in the .c file) and compile it according to the information in the Makefile. The output will be a hex file, which is the original file in 'computer language'.
7. In order to run Neil's program, you also need serial. You can get python to download this for you by entering the following into the terminal:
python easy_install serial
it should download, and then install and reboot the computer.
(if you don't do this, then at the next step, it may say: ImportError: No module named serial 8. Then use the command $ls /dev
this should provide a list of ttys and pty's. Look for tty.usbserial-xxxxxx where xxxxxx is a different ID each time. Here is was tty.usbserial-FTG5I76D 9. Now you can run: python hello.load.45.py /dev/tty.usbserial-FTG5I76D