Posted in Bits and bytes

Teensy++ (AVR) PLC controller – version 1

Here it is! The AT90USB646-based homebrew programmable logic controller. It’s not quite a Simatic S7 (and it’s not even completed in most parts), but it’s a nice start. A more complete and IEC-ish environment on the development software part (among many other things) would be nicer, but… the code is (will be) here, so extend it to whatever you want. But, whatever you may want to do with it, keep in mind it’s more of a “proof-of-concept” thing than a production-ready device.

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Posted in Bits and bytes

The PLC update

After looking at the Beremiz iec2c compiler source, I decided that modifying it to fit into this project is probably not the way to go. At this time, I’m deep into experimenting with the Coco/R framework on Java to produce my own IEC compiler. To make things simpler, I decided to support

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Posted in Bits and bytes

The homebrew AVR-based PLC – the introduction

Few years ago when I was searching the net for similar projects to gather some stuff for my potential graduate thesis, there was just a plain void. On techie forums ocasionaly some excited novice popped up with greeny questions about what would take to make a PLC, etc., just to get a bunch of “smart” answers about how stupid one has to be for trying to make something that someone somewhere can eagerly sell him. Not much useful, indeed. Sure, people wrote about projects and “PLCs” they’ve made, but almost all of them were just a kind of a relay…

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