Atmega128 is quite powerful microcontroller giving enough I/Os, memory and interfaces. Don Carveth some time ago constructed a megameter – a multipurpose device based on this microcontroller.
Together with PC interface megameter has a nice bunch of features including:
- Two 0 – 10 VDC voltmeters;
- One 0 – 30 VDC Hi-Z autoranging voltmeter with x10 jumper to give 0 -300 VDC range;
- 0 – 3 Amps high side ammeter;
- 4 channel logic analyzer;
- Frequency generator – 50% duty cycle square wave, 0 – 5 VDC, uC clock with divider, 1 Hz to about 8 MHz;
- Waveform generator – sine, triangle, square wave, 1Hz to 20+ MHz;
- Frequency counter;
- +5 VDC supply – 200 mA available;
- -5 VDC supply – 300 mA available
Board communicates via RS232 interface. If you will decide to replicate it – it should be easy to upgrade to USB with simple USB-TTL converter. [via]
