BoeBot+Xbee
average joe
Posts: 795
I've just finished rebuilding my BoeBot and now looking for some thoughts on what can be done with xbees. I wish I had access to a PropBoe, but can't afford one right now. Can you guys recommend somewhere to start?
Input much appreciated!
Input much appreciated!
Comments
Get the xBee Guide and look at the documentation for the products mentioned above and you'll have all the information you need.
Thanks for the input.
I was planning on using a 3v3 regulator for xbee power and 2.7k for xbee RX from BS2 pin.
I found http://forums.parallax.com/showthread.php?100656-Xbee-with-BoeBot&highlight=xbee+boeboe but it looks like he's using a ServoPAL
You can do a lot with a QuickStart board. Jose used one to control his BOE-Bot.
I have a PropBOE-Bot that can record and play back a path created by using a RC remote. You could do the same thing with a QuickStart by adding a SD card to it (you could probably do the same thing without a SD card by writing the information to EEPROM instead of a SD card). (You don't need to recreate my bot; I just wanted to point out not all the features of the PropBOE are needed to make a good robot.)
A QuickStart lets you use all the Prop's I/O pins. It can do a lot. Jeff has a sale that includes a "Servo&More" PCB with every QuickStart he sells (a very good deal IMO).
Do you know if a resistor is enough to protect the XBee from the 5V BS2 logic? (I thought PJ said resistors weren't enough.)
NO! You cannot do that, the XBee literature confirms - the XBee inputs do not have clamping diodes on their input pins.
Please refer to page 18 of "Getting Started With XBee RF Modules":
2: Parallax XBee Adapter Boards
The XBee module is a 20-pin DIP package with a 2 mm (0.079 in) pitch between pins. With typical breadboard and solder board hole spacing of 2.54 mm (0.1 in) the XBee requires an adapter for use
with these boards. The XBee is a 3.3 V device, as is the Propeller chip, so interfacing between the two can be done through direct connections. Interfacing with the BASIC Stamp and other 5 V controllers requires line conditioning between the controller’s 5 V output and the XBee’s 3.3 V input pins.
However, the XBee’s 3.3 V output can directly drive a controller’s 5 V input logic. Additionally, a regulated 3.3 V supply is required to power the XBee. Finally, to access the XBee from the PC for communications or configuration a means of serial interfacing to the computer is needed, such as using USB and a serial interface IC. Parallax has developed a series of interface boards for the XBee for ease of physical interfacing, signal conditioning, power requirements, and computer connectivity.
BASIC Stamp and other 5 V Controllers
The BASIC Stamp and other 5 V controllers need an adapter that:
* Uses the 5 V supply available to provide regulated to 3.3 V for the XBee supply power.
* Conditions the 5 V logic output to 3.3 V for input to the XBee.
The Parallax XBee 5V/3.3V Adapter Board and the XBee SIP Adapter Board provide both these functions along with pin headers suitable to 2.54 mm (0.1 in) breadboards and solder boards. They contain a 3.3 V voltage regulator and a 5 V to 3.3 V logic buffer.
As I said, the BS2 BOE is a bit underpowered for the things I would like to do right now. Cash it a bit tight so QuickStart and PropBOE are out of the question. If I had more time, I'd build a board with one of the Prop DIPs I have.
The BS2 BOE will work for running my wife through the Stamps in Class curriculum. She's taken an interest in my hobby so that's nice
I was looking for something cool I could do using xbees. Guess I'll need to wait till next year.
@PJ
Thanks for the note on the xbee NOT having clamp diodes! I had not actually got that far, thankfully.