I mentioned previously that I was waiting to see how my first DorkbotPDX board turned out before I sent and USBizi module boards out for production. I just got the last pieces I needed to put it all together, and here’s the result.
The board is extremely simple, it provides a .1" header, 4P4C connectors (x3), and the one pullup resistor required for a Dallas/Maxim 1Wire bus. All you need to do is connect VDD, GND, and DQ (any FEZ digital pin), and you’re off to the races. Here, I’ve got two DS18B20 temperature sensors attached, but any 1Wire device could be used (parasitic-mode power would require additional components).
I’ve also got a driver for the DS18B20 sensor, as well as a little class that wraps up GHI’s OneWire class for scanning the bus for devices. I’ll post it on the code site when I clean it up a bit.
Love the boards. What footprint is the RJ connector - I ask because I have a handful of connectors with nowhere to go, and a bigger handful of DS18B20’s with plenty of ideas where to go but nowhere to plug into.
I’ve never really cracked a good design for the one-wire libs - I always thought it’d be ideal to have the code for the “one-wire network” resilient to removal and additional insertions, as well as things like get-current-reading(device) and get-current-reading(all). I also wanted “soft names” so I maintain a big list of name vs ID and scan that - adding new ones as needed if a new node needs to get added or it’s “name” (location) gets moved. So I’m hanging out to see your code !
At the moment I have a 1-wire network of about 20 mixed sensors (ds18s20, ds18b20, ds2438). I can plug them in and the soft picks them up automagically. The readings get stored in an SQL2008 database, and that where I map sensor ID’s to locations.
I still need to finetune the software side because occasionally i see a temperature of -32500°C in my db table, though there’s no sign outside of an ice-age
