Remove the computer: Xbee to Asus router

by __ew__ on Tue Sep 15, 2009 11:57 pm

My tweet-a-watt project is up and running. I have my receiver connected to my Asus WL-500G Premium v2 router via the FTDI USB cable.

I want to solder the Xbee receiver into my router like Limor did in her blog video but I don't know which Xbee pins go to which router pins.

Could someone who has this working help me map the XBee shield pins to the router serial header pins?

Thanks in advance.
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Re: Remove the computer: Xbee to Asus router

by adafruit on Wed Sep 16, 2009 10:22 pm

You can sort of see it here
http://www.flickr.com/photos/ladyada/34 ... 795495792/
(theres also more photos in the set)
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Re: Remove the computer: Xbee to Asus router

by __ew__ on Thu Sep 17, 2009 1:43 pm

@adafruit Thanks for the image. I tried gleaning the mapping from your video (and failed) originally.

Ok, looking at the really hi-res version of that photo, I guessing the connections map thusly:

XBee:
  • Brown -> Gnd
  • Yellow -> Rx
  • Orange -> Tx
  • Red -> Either Cts or 3v (which?)

Asus header (I'll call pin 1 the pin closest to the 'J4' label on the asus board):
  • Brown -> Pin 2(???)
  • Yellow -> Pin 3
  • Orange -> Pin 4(???)
  • Red -> Pin 1

Can you confirm the XBee red wire for me? Seems it should go to 3v otherwise how would the XBee get power?

Also, any thoughts on the connections to the Asus header? The heat-shrink tubing makes it difficult to tell.

I'm also a little confused because the mappings on this image seem to have the CTS and RTS labels switched (Is the PCB label correct?)

Image

Thank you,

Eric.
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Re: Remove the computer: Xbee to Asus router

by adafruit on Thu Sep 17, 2009 1:57 pm

power is 3V, it wouldnt make sense to try and power it from CTS eh?
the red text is correct
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Re: Remove the computer: Xbee to Asus router

by __ew__ on Wed Sep 23, 2009 1:23 am

I now have my Asus WL-500G Premium v2 working with the xbee soldered into the serial header.

Photos:
The Asus serial header
The XBee wireless modem adapter

Pin mapping:
Code: Select all | TOGGLE FULL SIZE
Asus     Color   XBee
header  (photo)  header
---------------------------
pin 1   green    3v
pin 2   grey     TX
pin 3   purple   RX
pin 4   blue     GND


The serial port in OpenWRT is at /dev/tts/0
The baud rate is 9600
It seems to take a minute or so after booting up for the wattcher.py script to be able to communicate with the xbee.

See also:
http://lizard43.blogspot.com/2009/03/tweet-we-using-asus-wl-520gu-and-xbee.html
Image
OpenWrt serial pin chart for the WL500GPV2
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Re: Remove the computer: Xbee to Asus router

by adafruit on Wed Sep 23, 2009 9:04 am

fantastic work! and a nice clear photo :) im sure he'll will find it ultra helpful
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