Tuesday, January 31, 2012

MRF24WB0MA Not Working... Yet

I tried the test sketch from the i/o Blog, and... nothing! The Script got stuck in the initializing() function, and kept resetting every few seconds. I added a little debugging to narrow it down, looks like it just won't connect. To do:
  1. The wiring: I need to check everything, I really thought it was wired up right. Also I wonder about grounding more of the module's pins, to be closer to the WiShield schematic (right).
  2. The module might be having a hard time talking to my AirPort, so I'll try turning off security for testing. If that doesn't work, I'll try setting up a second network with one of the misc. wireless routers I've got in the digital dustbin.
  3. Look around for other simple example sketches, there might be more info on this module and Arduino in the links I scraped together for the first post on the module.

Wednesday, January 4, 2012

MRF24WB0MA Breakout

I soldered this up last night, using an EAGLE CAD board layout to guide me. The headers are set up and labeled and I'm ready to use the example from i/o blog-- more tonight!

Tuesday, January 3, 2012

WiFi Module for Arduino Projects

Microchip offers a small (21 mm x 31 mm) WiFi module-- the MRF24WB0MA (rolls off the tongue, eh?), datasheet here (pdf)-- for under $24. Talking to it looks straightforward, and a few people have folded it into their projects with great results.

THANKS to the fine folks at Farnell (Newark if you're in the US, like me), I find myself with one of these amazing little modules, and I'm starting to explore using it in a project or two.

The module is wired up for easy use in the products listed below (and probably more), but the prices all seem high to me given that you're paying more for the supporting circuitry than for the WiFi module itself:
  • AsyncLabs used to sell a few products based on the MRF24WB0MA: the BlackWidow Arduino-compatible board ($75), compact YellowJacket ($55) Arduino-compatible, and the WiShield Arduino shield ($55). AsyncLabs stopped sales last March, but fortunately EAGLE-format schematics and board files are still online (eg. WiShield V1 and V2) and the library for Arduino too.
  • Diligent sells a PmodWiFi ($60) module with a 12-pin (2x6, .1" pitch) header.
  • Microchip sells a Wi-Fi PICtail/PICtail Plus breakout module ($60) with a 28-pin (2x14, .1" pitch) header,
  • MikroElektronika has two options using MRF24WB0MA's: WiFi PROTO ($54) and EasyWiFi ($59).
  • OpenPICUS sells the Flyport module (€49, ~$64) which includes a Microchip PIC 24F and has an IDE for programming as a standalone module.
  • Seeed Studio sells the WiFi Bee ($70) with 2.0mm XBee header breakouts and an ATmega328 on board.
I first saw details on using the module on its own on i/o Blog, where Manis chronicled his success using the module with minimal components, building a stripped down version of the AsyncLabs WiShield and building a sketch with the library. More on that in the next post...