What is xB-Buddy?
xB-Buddy is the compact, cable-less version of FTDI cable, combined with XBee breakout board. Just plug the unit directly to USB Port on the PC, laptop.
xB-Buddy is not only useful for programming Arduino clone, but also a great device to communicate with any TTL serial device, such as a microcontroller to computer, GPS data, etc.
xB-Buddy also provided the sockets compatible with XBee modules, Standard or Pro Series (1 and 2.5), the same socket that is also compatible with RN-XV WiFly Module (WI-FI module with 802.15.4 architecture)
That's an Idea!
I got the idea from my hack, Convert FTDI Cable to "FTDI Dongle" for XBee Adapter. It shows how to modify the FTDI cable to use with XBee Adapter. But I went a little further, by placed the FTDI FT232RL usb/serial chip onto the board instead of using the third party breakout board as shown in the instructable.
xB-Buddy kit consists of a PCB, one and only SMD components(FT232RL usb/serial chip). All others components are through hole type components.
In my vision, xB-Buddy is intended to be an unassembled kit. It would be suitable for whoever want to gain the first experience with the SMD soldering, since there is only one SMD component included in the kit.
This might not be a good idea! Otherwise, it could be pre-soldered with pick-and-place machine from the PCB manufacturer.
Step 1: Design
xB-Buddy is in the prototyping stage, and PCB has not been produced or available before. The schematic design was adapted from Sparkfun's XBee Shield (WRL-09976) and AdaFruit's FTDI Friend (ID: 284).
First, I used EagleCAD software to create the schematic and board. I want to make the board as small as possible, so it would be light enough not to create too much load for the USB connector when inserted. And ended up with the size of 1.92 x 1.06 inches (48.768 x 26.924 mm) which is not included the extended USB header. The height of the module should be approx. 0.4 inch (10 mm).
I also send the Gerber files to BatchPCB.com to check if my design would passed, and it did. I also added the Eagle Files, and zipped Gerber files below.
Then, I read about the sponsor of the instructables' Kits Design Challenge, UpVerter's schematics design application on the web.
I was able to finish the xB-Buddy schematic within , using the printed reference from Eagle files, as the first time user. It is a really neat app. The app also provides the Bill of Materials in the csv format.
Here is the link to the dashboard to view the xB-Buddy schematic. http://upverter.com/sath/155d4df4a872df29/xB-Buddy/
NOTE: Eagles Files are provided "AS IS" under CC attrib/sharealike licensed. The files are still the work in progress. I shall not be liable for any risk or damages that result from the use of, or the inability to use, the files.
Step 2: Kit Components
C1,C2 - 0.1uF Ceramic
C3 - 10uF 6mm dia. type CPOL-USE2.5-6
LED1, LED4 - Red 3MM dia. LED
LED2, LED3 - Green 3MM dia. LED
R1, R2, R3, R4 - 1K Ohm R-US_0204/5 type Resistors
R5, R6 - 10 Ohm R-US_0204/5 type Resistors
J1, J2 - 2mm 10pin XBee Socket
JP1 - 6-pin Right Angle Female Header
X1 - USB Male Type A Connector (USB-A-H)
U1 - USB to UART Bridge - FT232RL type FT232RLSSOP 28-pin
Note: XBee module or RN-XV WiFly module are not included in the kit.
Step 3: Assembly and Resources
The needed tools:
Solder (lead-free is preferable)
The hardest part would be soldering the FTDI chip on to the board. If you are new to SMD soldering, I would recommended to do some research or study the tutorials of how to solder the SMD components before get your hand on it.
Here is the list of sites that offer such a tutorials,
LOW COST SMD SOLDERING GUIDE
These are the four parts videos that I used as the references of learning how to do SMD soldering,
http://www.youtube.com/watch?v=QEEV3AZjRMM Part 1
http://www.youtube.com/watch?v=RPtLviWt06A Part 2
http://www.youtube.com/watch?v=JtAv3Le0eoA Part 3
http://www.youtube.com/watch?v=MvuRXWzk9_c Part 4
Following the first and hardest part, should be easy enough to solder all the other components in. Works on the components that close to the center first and moving outward.
Resources on XBee
XBee module and datasheet
Tom Igoe's XBee page
My XBee Configuration Video Tutorial.
Step 4: First XB-Buddy Prototype
The first prototype that I created was working properly. It's very bulgy, too tall. But I still am using the modules. I use it as a base module to send/receive command in this project, Make Wired Robotic Arm Edge to "Wireless" with DIY Arduino + XBee, as well as successfully using it to test RN-XV WiFly module.
xB-Buddy has been a proof that I will be using it more than any other TTL serial device for data communication!
Below is the gallery of photos of xB-Buddy first prototype and test.