The Vex controller needs a serial port that can be accessed by other MCUs similar to the Parallax RC Servo controller, that way we can make Vex Robots more autonomous.
fyi,
there is a user serial port.
I’m using it to talk to the CMU-Cam.
if there is one where is it
Where you plug the programming cable in, that is the serial port but you will need some sort of adapter to interface that with a regular serial cable.
You might want to use the TX & RX signals available at the top of the Digital and Analog I/O section of the Microcontroller
Yea, what are those ports for?
Read the title of this thread; then read my reply to tswift’s comment; then decide if you really need to ask what those ports are for. 
Blake
I thought that the place where you plug in the programming cable was a user serial port.
I didn’t think the rx and tx port were serial ports.
Both places expose the physical part of a serial I/O interface.
okay, the RX/TX ports are where the data goes when the thing is sent,
these stand for recive/transmit if you want to connect them to a serial cable you connect them:
RX+ on vex to pin 3 on a standard DB9 cable (recive)
RX- on vex to pin 5 on a DB9 cable (data standard ground)
TX+ on vex to pin 2 on a DB9 cable (transmit)
TX- on vex to pin 5 on a DB9 cable (data standard ground)
RS232 DB9 pinout
the vex rx goes to DB9 tx so the DB9 transmits and the vex recives…
same on the tx vex and rx DB9…
othrewise they clash and can’t ‘talk’
Ie: transmitting to transmitting
here is a data sheet:
I think you can do get it, I just got the concept 2 monthes ago.
Be careful though: Both the programming port and the Rx/Tx ports use TTL voltage levels NOT RS-232 voltage levels. If you wire the Vex directly to a DB9 and plug it into a computer you may fry your Vex.
The first and last posts in the serial port FAQ thread make this point.
Use a level shifter board like this or a cable like this to hook a Vex to a PC.
Cheers
- Dean
You need to connect the Vex Controller’s serial Rx and Tx signals to a serial driver such as a MAX233 if you want to connect it directly to a laptop or PC serial port (COMx). On the other hand if you want to connect the Vex Controller to another micro-controller that supports a Serial Communications Interface (SCI) then connect the Vex Controller Tx → Rx micro-controller and connect the Vex Controller Rx → Tx micro-controller as long as the micro-controller is a +5 Volt device.