Printed circuit board design, AVR microprocessor, USB, C/C+, Atmel

Closed - This job posting has been filled and work has been completed.
Hourly Job
Part Time
Less than 1 month


Key skills/experience include the following: printed circuit board design and manufacturing, microprocessor (Atmel AVR attiny) programming, C/C++ programming, obdev USB code, PC/device GUI programming.

Design a circuit board for a small photometer. It measures light absorbed or scattered by a liquid. Please see the attached PowerPoint for more information.

The circuit is connected to a PC using a USB cable, which provides power to the device and also sends output data to the PC. The USB connection is through obdev code.

The circuit generates a voltage output that is proportional to light. The microprocessor reads this voltage and sends it to a PC. The microprocessor is an ATTINY 45 chip. The PC software looks like an oscilloscope, reading the voltage input vs time.

First drafts of the firmware and PC software are provided. The GUI would need some customization to change the "look".

The photometer has 1 LED. It also has spaces for 2 detectors, one in-line with the LED light and the other at right angles. The detectors are Taos light-to-voltage converters, such as the TSL257.

Skills: atmel, avr, C code, firmware, PCB production