So after aquiring some of the Futaba Female J connectors, some servo wire and a breadboard from Radio Shack, I assembled this.
Click on the image for a larger pic. Let’s go to the video!
You will notice that I have configured an LED in this example. You must have the programming kit to do this and you have to either use a port that is defined as output 12-16 I believe or reconfigure the ports. To do that you double click the include line in the code display window. You’ll get a configuration dialog. You click on the port to change it’s direction. Use the digital out block to turn it on and off. This also works with the 6v piezo buzzer from RS as well. Now I just need to find some red acrylic…
The bread board gives you the connections you need to build your own sensors or output devises. If you know anything about electronics it’s a handy way to prototype circuits. This circuit provides an output to light an LED.
The connector plugs into the control unit and provides 5 volts(red), ground (black) and input/output(white).
If you plan on building robots you might want to learn something about electronics. There are some great books here. Forrest Mims wrote a series of books that sold, until recently, at Radio Shack. They were basic electronics circuit designs.
Here is a pic of my breadboard. I am playing with an 18f4550. I am thinking about driving the VEX motors with it.
I use the MPLABS C18 compiler with both the VEX controller, and the 18f4550.
I have the 18F4550 “talking” to my PC via RS232 via a MAX232 chip. I am learning about PIC interrupts. I have a VEX switch on RB0, PORT B bit 0. I have a .1uF cap on the switch for debounce, though I don’t have the cap grounded in the picture.
The PicKit2 programmer shown in the picture is a $50 ICSP programmer from Microchip. The programmer now works with most of the 18F series PIC’s.
If I get a robot running with this PIC, I will post pictures here.
Oooops! I deleted the directory these pics were in. I put it back. I’m thinking I haven’t been playing with my Vex kit in FAR too long. Time to go dust it off.
It’s a bit late but…
The red wire is the positive side of the power supply, it’s not used in this example.
The black wire is the negative or ground.
The white wire is connected to a port on controller ic which can either read 1 or 0 or write 1 or 0. Some of the ports can write 1’s and 0’s in pulses but that another discussion. 1’s are 5 volts 0’s are well zero volts.
The way it works is…
Your code tells the controller ic to turn on a port making 5 volts appear on the white wire.
The signal goes through the resistor, which limits the current so you don’t blow up the controller ic.
Through the led and on to the ground completing the circuit and turning on the LED.
Almost anything that can be turned on and off with 5v will work here.
LEDs, relays, piezo buzzers, UV LEDS.
I used the Microchip dsPIC30F6014 micro-controller for my VEX Power Glove and Wireless Joystick Controller that will allow me to control my Hero 2007 Robot and Gilbert III Explorer Robot. Currently I am developing a Programmable Controller for my Vexplorer robot using the SchmartBoard rapid prototyping system for soldering surface mount technology components (SMT). Some links to my dsPIC based robot controllers are provided below:
You can see the progress I have made at the SchmartBoard site, where I am a developer and include the complete schematics necessary to build the DC Motor Controller, Wireless Joystick Controller and Animation Controller. SchmartBoards are the Vex equivalent of DIY rapid prototyping boards used for Surface Mount Components (SMT) that seem to be prevalent these days.