The Funky v2 is a miniature Arduino Leonardo clone with RFM12B module, intended for low power, battery operated remote node. Due to the miniature size, only few carefully selected pins are available as a side header, none the less that is more than sufficient to interface several sensors at a time.
Having gained experience with my Funky v1 project, I decided to create a new version. The project is a success, yet the areas I wanted to optimize are
The Attiny84 MCU that was used in the Funky v1 has limited RAM and sketch memory The Attiny84 requires an ISP programmer for sketch uploading The Attiny84 required a modified Arduino core Many of the available Arduino libraries are not compatible with Attiny84 So the Funky v2 was created, see my posts here , here and here
Board size is mere 22×22.8mm (0.87″x0.89″) in size (same as Funky v1) The MCU used in an Atmega32U4, the same MCU that Arduino Leonardo uses. This makes the Funky v2 a minuature Arduino Leonardo compatible board with RFM12b module The Funky v2 has the Caterina bootloader, so programming is done with Arduino IDE via micro USB Uses external 8Mhz crystal (can switch to internal RC clock in software as described here) Operates on 3.3V
Read more http://harizanov.com/wiki/wiki-home/funky-sensor-v2/
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