i found thissite on vexfan theres a couple of videos on this link i dont know how but this guy used 2 microcontrollers or how he connected them i dont know if this will answer your question or not but here you go its a realy cool robot http://metweb.spsu.edu/staff/jhudak/robotics/
Vex Controllers are not easily networked since they use the UART serial port for downloading Easy C Vex applications. It is unfortunate that the I2C and SPI ports are not accessible since they could be used to network up to 128 Vex controllers via the I2C protocol.
You may need another more powerful controller to handle your Triangulation and navigation algorithms and be able to connect more sensors. The new 16-Bit Microchip dsPIC30F4011 or dsPIC30F6014 MCUs have 30 MIP (120 MHz) processors with built-in Digital Signal Processing (DSP). They can be programmed using dsPIC30 C with the ICD2 and MPLAB.
I am planning to use my new Biostamp III board, that is based on a dsPIC30F6014 for my Sensor Controller Board (Sensor Subsystem) on the Hero 2007 Robot. In addition I am using a Vex Controller and a Biostamp II, which uses a dsPIC30F4011 MCU for the control of the Vex, motors (Motion Subsystem). These modules communicate with the robot’s onboard laptop Master Controller via the COM3, COM4 and COM5 serial ports.
I am currently developing drivers for a $24 Pololu 8-servo Serial Controller that can control up to 8 Vex servos or motors, that I will use to operate the Hero 2007 in autonomous mode.
The Vex controller has been invaluable in developing, calibrating, aligning and rapid prototyping my robot and I will still use it for tele-robotic control of the Hero 2007 and the arm when it is completed. You can see the progress I have made at the following link:
the microcontrollers are probably working independently but in a coordinated way through clever programming. one of the microcontrollers had the label " legs" on it. I guess one handles such and such subsystems while the other operates the remaining components.this is comparable to the human brain: somewhat split with each side controlling a part of the body and assuming specific functions but acting as a unit. anyway, just a personal scenario…
Two or more Vex micro controllers working together.
This is the one area of Vex, that I think has some real development potential.
First read up on some background info, all of these links have some peice you will most likely need:
**You will need to wire the two Programming Ports (or TX/RX ports) together. You will need to develope C routines for handling the Serial Data. You will need to create a message passing scheme, preferable with Checksums and Acknowledgements. You will need to develope a message systems in each “brain” that can “execute” the messages from each other or from a master.
It is VERY do-able…
That is the first walking robot i have seen, and it is amazing.
That is awesome. I have a question though. Are the motors that you used vex motors?
i didn’t make the robot i just found it on vexfan but im preaty sure they are vex i think its all built out of vex exept for the orenge things on the feet and the blue mouth
It this is VERY do-able…
Terms you will need to understand: TTL (as it relates to the following terms), RS-232, RS422/RS-485, I2C, SPI.
The Problem is that with standard Serial Ports on the Vex, they are TTL, and can be changed to RS-232 (with the Vex Programmer Module), which means that Only Two ports can be connected together.
I have though of a way to connect multiple devices (e.g. Vex Modules) with TTL, but there is a “criticle” downside… If one Vex Module fails, they all fail…
One thing you can do is to use an Linux or Windows CE based embedded controller board with lots of serial ports (SBC), but these controllers can cost anywhere from $100 to over $1000 and require you to use either GNU C/C++ or Microsoft Embedded Visual Basic eVB or Microsoft Embedded C++ eVCPP for software development. Another alternative which I am using for my Hero 2007 Robot is to use a laptop with over 5 serial I/O lines using USB to serial converter cables that are available at Radio Shack. I can communicate with multiple controllers including Vex, Microchip dsPIC30F6014, Parallax Stamp BS2/BSX and Pololu 8-Serial Servo Controller (SSC).
Using this method you get some degree of fault tolerance unless the main controller goes down. If you really need robust NASA endurance for your robot’s electronics, you might consider looking into Tripple Module Redundancy (TMR) or even N-Module Redundancy (NMR) with voter logic.