Thursday, February 28, 2008

Breakout Board Order

8 x 2mm 10pin XBee Socket (SKU#: PRT-08272) = $10.00
4 x Breakout Board for XBee Module (SKU#: BOB-08276) = $11.80

Sub-Total: $21.80
Shipping & Handling: $3.30
Grand Total: $25.10

Total project cost so far is $426.28.

XBee Order

3x XBee Series 1 at $19.00 each = $57.00
4x thermistor at $0.13 each = $0.52
4x thermistor at $0.15 each = $0.60
4x thermistor at $0.13 each = $0.52
Shipping = $6.69
Total = $65.33

Total project cost so far is $401.18.

Friday, February 22, 2008

Even more progress

Thursday Update

Since we got the USART working last time, our goal today was to start using the XBees with the Butterflies. First we set up the XBees with the development boards and had them broadcast to each other; then we set up the Butterflies with MAX232s and had them receive a broadcast from one of the XBees connected to a dev board. Writing this makes it sound quick, but it most certainly was not. But we now have a true point-to-multipoint network setup.

And we did some other stuff but it's late and I want to sleep.

More progress

Tuesday Update

We got the Butterfly's USART working. We are now able to send serial data to and from the Butterfly at 115k baud (the highest rate the XBees will be able to use) with 0% error. This allows us to easily test the ADC by having it spit readings to HyperTerminal. It appears the ADC is fully functional.

We also worked on the pre-amplifier for the ADC. The voltage levels we get out of line level MP3 players and audio jacks seems to range between 0-0.3V. The ADC can read values between 0-3V. So in order to utilize the ADC's full precision, we will need to amplify the input by a gain of about 10, we think.

Thursday, January 31, 2008

Progress!

01-31-08: We've mostly figured out the A2D. ADMUX is used to pick the input channel for the mux (we're not sure what physical pins the channels correspond to yet). ADC stores the converted data. We also got the LCD to display text.

Next time: use BitScope to find which pin we're reading.

Tuesday, January 29, 2008

Friday, January 25, 2008

ADC sample code

Here is the site where some ADC code can be found. It's inside the 0.7.2 zip file as ADC.c.

I put the AVR Studio installer (aStudio4b528.exe) on the Memorex flash drive. It's 73Mb and you have to register on their site to download it, so you can use that if you want to save a step.