Sunday, March 11, 2012

MRF24WB0MA Wifi board update.

Success!
(For various values of  'success' at least)

I finally have the board physically put together:

Not pretty, but I think it will work.

After drilling the pcb holes for the .1" headers, I am now certain that surface mounting was the way to go for the daughterboard. I never would have been able to get the accuracy needed with my uber cheapo drill press, it actually moves about 0.5mm when you apply too much vertical force to the press, so about half way through the job I realized that slow drilling was the key to better accuracy. Still, I don't think I could pull off drilling holes for 0.05" headers.

To do a surface mount solder, I "pre-soldered" the pads where the board would be sitting:





I then applied liberal amounts of flux to the pads. Flux really is key to getting decent solders, it took me a while to realize just how important it is. Then I carefully placed the daughterboard on the pads. I melted a small amount of solder on my iron and then used the iron like it was a paintbrush, and carefully "painted" solder into the daughterboard grooved pads.

I did extensive connectivity testing throughout the process, but I did not test it after final assembly, because I wasn't sure what kind of voltages my meter was using, and I didn't wan to risk damage to the Wifi module from accidental reversed polarity.

Anyways, I've got a pic24 with 128k of flash, and I'm switching over to software mode for the next step, to get the Microchip TCP stack up and running. This is my first venture into the PIC line of MCU's, so there's a little getting up to speed. I will say that I just installed MPLAB x, and it is a *huge* improvement over the old MPLAB IDE.

--P


4 comments:

  1. Do you think I can connect the WiFi chip to a LPC1768 without using the Microchip library?

    ReplyDelete
  2. I think it's possible, that chip certainly seems more powerful than any 16 bit PIC. You may have to port Microchip's code over to ARM though. Be careful if you attempt that, because Microchip's license for their TCP stack is a little restrictive in what you can use it for in a commercial product with non-microchip hardware.

    Also check out these blogs:

    http://jmsarduino.blogspot.com

    and
    http://theiopage.blogspot.com/

    Where they are getting the board to work with Arduino, they might have code that is easier to port to ARM. They've also taken a much more pragmatic approach to mounting hardware than I.

    --P

    ReplyDelete
  3. I am trying to interface MRF24WB0MB with PIC, can any one help me with the commands for MRF24WB0MB?

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  4. @Anon, I don't believe Microchip put's outs a "spec" per se for the Wifi board. The closest thing I could find was the source for the PIC TCP/Wifi stack libraries that Microchip provides (with a rather restrictive license), that sort of diminishes the value of this board. There are some project out there on the web where people have managed to get non-PIC micros to talk to this board. Check out the links in http://bytecruft.blogspot.com/2012/04/wifi-links.html.

    ReplyDelete

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