Here's the specification http://www.sdi-12.org pdf
And a schematic:
Checked some instruments and oh my they were expensive! This is the cheapest I've found Decagon 5TM
@alexanderbrevig started
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
Here's the specification http://www.sdi-12.org pdf
And a schematic:
Checked some instruments and oh my they were expensive! This is the cheapest I've found Decagon 5TM