PBP projects for R/C models

[Kenjones1935]

OKAY,

I have discovered through the use of my oscilloscope that PAUSE stops the HPWM output pulses. In order to emulate the radio system I want to try giving the ESC two seconds worth of neutral PWM between switches back and forth between forward and reverse. This is a race car. It will not be going backwards very often, but it is necessary sometimes. Looks like I need to figure out how to set a two second interrupt. Hmmmm. NUTS!

Ken

[ScaleRobotics]

I have discovered through the use of my oscilloscope that PAUSE stops the HPWM output pulses.

Hey Ken, welcome back to town.

Do you mind posting some of your code for us to figure out what is going on? The HPWM command, or using the CCP hardware PWM with your own commands should both work independently of your code. I have a 2 second pause that is repeated, but HPWM keeps pumping out pulses the entire time. But if I repeatedly call HPWM and set it using PBP, it can give me some screwy results. Probably better setting the registers directly, like Bruce shows in this example: http://www.picbasic.co.uk/forum/show...1478#post61478

What PIC hardware are you using?

Thanks,

Walter

[Kenjones1935]

Here is the first couple commands of my code. I deliberately start HPWM then PAUSE for four seconds. My oscilloscope shows a flat line for four seconds then springs in PWM action.

I just looked at it again. I am no longer as certain as I was. Once I get into my code it seems to behave as I expect. I'll get back to you all tomorrow.

Thanks, Ken

[Kenjones1935]

The outputs of PORTC.1 and PORTC.2 are high all the time.
Why? In other code snippets PAUSE seems to allow action to continue. I hope you guys see that I am being stupid.

' PORTC.0 'High is R/C.  Low is PIC control
TRISC = %11110000

main:
low portc.0
gosub straightforward
pause 4000
goto main
end

StraightForward:
pwm 1,120,50
pwm 2,120,50
return

[Kenjones1935]

As soon as I typed "submit" I saw that I had left out the H in HPWM. Thank you sooo much!

Ken

[Kenjones1935]

First I used my 44 pin PIC (with no PICKIT 2 board) on a toy level car. Toy level means bang-bang control. It worked.

Now I am running a model level car with PWM control. I miss wired CCP1 and CCP2. Steering was going to the wheels. Driving was going to the steering servo.

I thought I had double checked this. Clearly my double checker was flawed. I shall rewire and report back.

Thank you for your patience.

[Kenjones1935]

Yup,

Now when it sees something in front it stops then goes backwards. And when nothing is in front it goes forward for all its worth. Such a difference getting the steering servo and the wheel electronic speed control signals actually going to the servo and the ESC.

Now to calibrate HPWM for this fancy ESC. It seems very similar, but not exactly like the old not-so-fancy ESC. There are still funny rules around switching from forward to reverse and visa verso.

Ken