Talking Multimeter Project

 

 

Rachel Dipirro and Jonathan Lo made an interesting Talking Multimeter Project for their Cornell University ECE 4760 Final Project. The multimeter is built around a PIC32MX250F128B. This is not a robust product that will be replacing your desktop multimeter since the range is not that great. For example it can just read resistance between 0 and 50K and voltage up to 10 volts. This range is fine for lots of work and the measurement front end could easily be swapped out with a high resolution ADC to greatly enhance this.

The multicolor LCD display is a great way to display the output and the number pad is perfect to control the system but of course the heart of this project is the voice output. The speech synthesis is performed by transmitting data to an external Microchip MCP4822 SPI DAC, the samples that are played are 16kHz samples that were compressed and stored onto system flash.