Color Reader

I had a problem where when I point a flashlight at the sensor I see 0xFFFFFF on the iPod Touch, but every second or so it would drop down very low numbers. I was looking into possible problems in the assembly code produced by Java Grinder but it looked great.

Anyway, it finally hit me what's probably happening. The flashlight must be PWM'ing and the circuit is picking that up. I hooked it up to an oscilloscope and put the flashlight on low brightness and saw clear PWM going on on the scope. I put it on bright mode (which I was testing the circuit on) and there it was.. PWM also. Not sure why anyone would PWM a flashlight turned on full power (bug?) but it appears this is the issue.

I might make a video of that later...

iOS app written (pretty rough still). I am getting color information over Bluetooth BLE now. Kind of disappointed in this sensor though. I had a choice between the $24 SparkFun color sensor and the $53 Parallax sensor. Really wishing I got the Parallax sensor. It has 2 bigger LED's and a lens.

I got the rest of the circuit soldered and added UART support to the AVR8 module of Java Grinder. Next step is to use the already implemented ADC code to read the color sensor and send the values over the UART.

Got a prototype PC board from Gateway Electronics yesterady and my color sensor breakout board arrived from SparkFun. This morning I soldered the thing together (except for the wires to the color sensor) and posted a picture of 3 components (Trinket, color sensor, and Bluetooth BLE module) installed on the board. Next step is to update Java Grinder so the AVR8 generator can output UART.