need help with r/c model electronic speed control

[raimain]

i was thinking 1 chip would be better so it can do (channel mixing) to mix the throttel and the steering.

the motors that im using are standard 540 motors and standard 7.2v r/c batteries.

i had a look around and there is 1 esc in a microchip app note but its for a r/c plane so it has no reverse(AN847), but will probly be usefull for getting the code for reading the pwm from the reciever from.

i also have a load of TIP120 NPN darlington transistors to use, but not sure if they are the right sort for this project.

i hope that someone can help me with this project

[Dave]

raimain, I thought you might need some assistance so here is a circuit I came up with about 8 or so yeard ago to drive a BARBIE Hotwheels car for my daughter. The circuit as built can supply 300 amps surge and as built has no heat sinks at all. All you need is 1 pwm output and a direction bit. HTH

Dave Purola,
N8NTA

[raimain]

thanks for the circuit diagram, now i just have to build it.

does anyone know which chip would be best for this and how do i find the code that will work propely for this project.

thanks again

raimian

[Dave]

raimain, It may be a bit complex so here is the jistofit, I pulled every thing out but the important stuff. The variables SPD and DIR are 10 bit inputs from say a joy stick corresponding to Y and X. With two of the circuits I previously posted you can make a tank type device and operate it with 1 joystick. Pressing it forward to move forward and pulling it in reverse to travel in reverse. Naturally moving it left or right will the device turn left or right. The null position for the variables is 511 for no output from the H bridge.
This code was originally written for a 16F876 but updated for 18F252.
I'm sorry I can't give you more but that's business........ HTH....

Dave Purola,
N8NTA