Connecting the USB Mini Adapter to an XBee for Serial Communication

I explain on this page how to use a USB Mini Stamp 03 serial programmer with an XBee module/radio. A few important notes before you start. First, there is another serial programmer marked “Arduino Stamp 02” that is used with the Arduino Mini. Although it looks like the “USB Mini 03”, it is not. The 02 programmer doesn't have the DTR and RTS holes needed for firmware upgrade.

Second, any schematic you're looking at doesn't have pin numbers for the Mini 03. (As of the date of this writing, 7 July 2009, I was unable to find a datasheet for the Mini 03 with pin numbers.) So, to make the following discussion easier, I added my own pin numbers.

Thirdly, the XBee can only run properly on voltage ranging between 2.8 and 3.4. The 03 provides 3.3. Don't connect to 5.0 volts

And lastly, the Mini 03 programmer doesn't have male headers on pins 1 – 5 and 18 – 23. You'll have to solder those in before you start.

Now on to the parts list:

Parts List

Wire
Breadboard, available at Radio Shack
XBee module/radio, available at Mouser
Arduino Mini USB serial adapter/programmer, available at Makershed
XBee breakout board, available at Sparkfun
Momentary button. I'm using a button I found in a parts bin, but you can use any button or switch that closes a connection momentarily. If you can't find one, you can use a piece of wire to close the connection between ground and pin 5 on the XBee.

Pinouts

USB Mini 03 Serial Programmer Pin Numberings

XBee Pin Numberings

Connections

Note: the reset pin on the XBee should be connected to one end of a momentary button/switch, and ground should be connected to the other end of the switch.

USB Programmer	Pin #		Pin #	XBee
+3.3V	2	⇔	1	+3.3V
Ground	3	⇔	10	Ground
TX	6	⇔	2	TX
RX	7	⇔	3	RX
DTR	18	⇔	9	DTR
RTS	19	⇔	16	RTS
Ground	3	⇔	5	Reset

Final Thoughts

Your XBee should now be ready to talk serially to a computer, and to have its firmware upgraded with Digi's X–CTU software. If things aren't working, double and triple check your connections. In fact, you should carry out these multiple checks before your first attempt at connecting your new board to your computer. Crossing wires could damage your programmer and/or your XBee.

Roy Vanegas
Last modified: Fri Jul 10 13:09:32 EST 2009