XBee Explorer DIO ports support analog?

Wireless & IoT
1

I’ve been using the MakingThings XBee board:

http://www.makingthings.com/store/acces … board.html

http://www.makingthings.com/store/catal … image/418/

and it exposes ports 0-6 which can be analog input or digital I/O. Since the Explorer board ports are labeled DIO, I wanted to confirm that you can use these ports as analog inputs?

.phil

2

The picture of the board in your link shows pins labeled as AD0 to AD6.

These could be used for analog inputs.

Which pins will depend on exactly which XBee module series and firmware you have.

Did you also buy the XBee modules link to DigiKey?

XBee (normal) - $19, part # XB24-AWI-001-ND at www.digikey.com

If so these are Series 1 hardware with firmware to run the 802.15.4 protocol. Please verify.

The XBee’s pins will need to be configured to use them for analog input. Either look in the XBee document for the module hardware/firmware you have or post the module hardware/firmware versions for additional help.

3

That’s the MakingThings board picture. But the Sparkfun board just shows DIO for its pins. Look at this page:

http://www.sparkfun.com/commerce/produc … ts_id=9132

Thanks for the links. I’ve been using the Series 1 successfully with analog input, I just want to know if I can use them the same way using the board from Sparkfun.

.phil

4

Well I did misunderstand. The SparkFun board also just brings the XBee pins out so the labeling is just to identify the pins. When properly configured the DIO pins can be analog (depending the the XBee hardware/firmware).

SparkFun does have the schematic for the regulated breakout board that should answer any connection questions.

5

We’re having a problem with the XBee Explorer board. With a series 1 XBee, configured to send values from the analog inputs, the same XBee works great on the MakingThings board mentioned above, but with the SparkFun XBee Explorer, it always sends a value of 1024 regardless of input. Any ideas?

6

The Explorer board brings the XBee IO lines out to the 0.1" header just like the MakeThings board. I’d check that the connect for the XBee module is soldered correctly and that the pins in the socket are not damaged either from being crushed or too much solder flowing into them.

Does the series 1 board require an external Vref? or need Vref tied to VCC.

The MakeThings board has a trace and pads labeled Vref that the Explorer board seems to lack.

Are there other connect to the MakeThings board that are not on the Explorer? SparkFun does have the schematic available.

7

This has happened with two separate Explorer USB boards, so it seems unlikely that it is a soldering or other damage problem. I don’t know what the XBee requires, and frankly am not sure what to look for in the schematics.

I guess I’m wondering if anyone has gotten an XBee to correctly transmit analog input values where the XBee Series 1 is plugged into a Sparkfun Explorer USB and configured as an “end-device”? Has this been tested?

8

Can you get digital data from those pins? There is an internally enabled pull-ups on the digital inputs for a logic high, then just ground the pin for a low.

I’m suggesting trying digital as it is easier to troubleshoot. Only the digital inputs are working then it should be just a manner of changing the pin parameters to analog.

Are you sure you have the same input pin on the Explorer as on the MakeThings board? I’ve made simple errors like that enough times. The 0.1" headers on the two boards do not have the same pin-out.

The IO pins just connect to the the breakout header on both boards. So there isn’t any rational reason one doesn’t work.