Sound card communication with electronics

Demonstration of my sound communication protocol, which sends data at a rate of 9600 BAUD (at 48000Hz sample rate).

It consists of a PIC12F683 microcontroller with a DS1820 temperature sensor, and uses the computer's MIC input to send data to.

Protocol is as follows:
For a 1 bit, send "10100", for a 0 bit send "10000" where each timeslot is one sample (hence 5 samples per bit). The receiving software is a bit more complicated to compensate for the filtering effects going on inside the sound card, as well as aliasing effects from the non-precise timing. The error rate is practically zero (Not a single error in a heavy test with 24 million sent bits).

The temperature sensor is cooled by a TEC mounted on a CPU cooler (from an AMD XP 2400+ if you must know, and no, the TEC wasn't used in the computer the cooling fans came from.)

Category:

Science & Technology

Tags:

• Sound
• Audio
• communication
• protocol
• PIC12
• PIC12F683
• DS1820
• TEC
• One-Wire