VEX Transmitter to HC-8+

[JonnyMac]

The 300ma did NOT work.

You should always budget at least 500mA per servo.  Under load they require a lot of current.

[JackMan]

This does sound really cool. I don't have a VEX transmitter so I'm not sure how it's configured as far as servo travel limit settings. I would have to think this an area of concern when doing a live program with a finished prop. You could damage the servos if the sticks are moved beyond the mechanical limits of the servo linkage. This may not be immediately noticeable but running the saved program repeatedly could be trouble. 

[davisgraveyard]

You are correct about the making sure you trim the controller to set your servo limits.  It is also very important to practice using the controller for a while so you learn the optimal movement you will be using.   But the benefit is you can blend multiple servo movements doing the live recording that you just can't duplicate with a manual setting.   Adding just a little tilt movement while turning is hard to do manually.

[youngti]

I have been looking around and the only VEX transmiter that I could find is a Transmitter/reciver combo.  I found this on Ebay, http://www.ebay.com/itm/NEW-VEX-Robotics-Design-System-Transmitter-and-Receiver-Kit-with-torn-box-/271052951123?pt=Radio_Control_Vehicles&hash=item3f1c03ce53 lest expensive I could find.  Is this the correct hardware?

I too have three RC units (two FLYSKY adn one HITEC).  Do you know if there is a way to make these work.  I know they each have a trainer port, just not sure what type.

[davisgraveyard]

Jon,

What about something even more common?

http://www.logitech.com/en-us/gaming/controllers/gamepad-f310

A USB dual joystick?  If it were connected to a USB to serial adaptor could it be connected to the HC-8+ and then used instead of the VEX?  How hard would the code be to write?

[youngti]

yeah that would be cool.

[bsnut]

A USB dual joystick?  If it were connected to a USB to serial adaptor could it be connected to the HC-8+ and then used instead of the VEX?  How hard would the code be to write?

You would need to know the serial commands from the USB dual joystick in order to write code for the Propeller.

How about something even more common? A Atari or Nintendo joystick which is proven to work with the Propeller (HC-8+ brain) and here's the link to the Parallax Object Exchange for the Atari or Nintendo joystick driver
http://obex.parallax.com/objects/87/
which can be combine with the code that Jon wrote. 

[JonnyMac]

What about something even more common?

http://www.logitech.com/en-us/gaming/controllers/gamepad-f310

That will not work because the Propeller doesn't have the horsepower to be a USB master.

A Atari or Nintendo joystick which is proven to work....

We have a Wii interface module. That said, it fits on the HC-8+ where the uSD adapter goes; you can use one or the other but not both at the same time.

[youngti]

So I just bit the bullet and bought a VEX on e-bay for $59.  I am very excited to try this out on my latest project.

[JonnyMac]

Sadly, All Electronics sold out (at one time that had a couple pallets of them,  brand new in a box) -- $30 was a great deal.

I was very ill last week and am just getting back into the swing. Will get back to porting your VSA code to Vixen.

[youngti]

Not  problem, I appreciate the help.  I understand that you are busy as well and I ma glad your back in the swing of things.  Very excited about the HC-8+ and all the possibilities.

[youngti]

So I just got my VEX transmitter/receiver.  Question it came with the controller (receiver) and the transmitter.  Do I plug the modified phone cable into the trainer RJ11 port on the back, or do I use the Transmitter module which also has an RJ11 port.

If it is the transmitter module that is pretty cool, no long wire to the prop.

[JonnyMac]

I use a direct connection which requires just two wires. If you want to connect the receiver to the HC-8+ then you have to enable the +5v connection to the R pins of the SERIAL headers. If you look on the bottom of the PCB, there are two oblong pads between the serial headers and the TTL input headers. You'll need to short these pads together with a bit of solder -- this will provide 5v to the R pin which can be used to power the receiver.

Here's the connections looking into the receiver:



Vdd = +5v (R)
PPM = signal (W)
Vss = Ground (B)

[youngti]

Just an FYI, when I purchased mine off Ebay it did not come with a teather cable.  The port for this is not a RJ11, it is the thinner handset cable which you can get from Radio Shack shown here http://www.radioshack.com/product/index.jsp?productId=2102557.  Other than that it works perfectly.

[gmacted]

Oddly enough, I bought one of these VEX transmitters from All Electronics back in 2008 for $30 and it's been sitting in my closet ever since (Still in the box of course).  I've also been using a Prop-SX to control my 3-axis skulls.  Now it looks like I'm going to have to buy an HC-8+ and see what this thing can do.  THANKS JON  >:(