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Tumbler
03-27-2010, 01:16 PM
Hello

I'm searchin for a PWM Pal -like chip or module.
The parallax pwmpal has only 4 pwm outputs, i need at least 15

Anyone knows such one?

@parallax: is it possible to order a modified pwmpal with 15 pwm outputs? I don't need the inputs. Only the serial link bs2<>pwmpal (PINO)

Mike Green
03-27-2010, 01:24 PM
You could use 4 PWMpal modules, all mounted separately from the Stamp, and control them using 4 Stamp I/O pins, one for each. Since the PWMpal blocks the use of 4 Stamp I/O pins, this would actually free up one I/O pin for other uses.

You'd connect all the PWMpal Vdd, Vss, and Reset pins together to the same pins on the Stamp. Each PWMpal's P0 would be connected to a separate Stamp I/O pin and the 4 output and 4 input pins of each PWMpal would be available for connection to your devices.

Post Edited (Mike Green) : 3/27/2010 5:31:23 AM GMT

Tumbler
03-27-2010, 01:41 PM
I had the same idea Mike, but it will a little expensive for my project.

Looking at the sx20 sheet, i see it has 12 input/outputs, but couldn't find if they all can programmed as pwm outputs.



But thx for answer this

Mike Green
03-27-2010, 11:59 PM
A cheaper way would be to take a Propeller Servo Controller and modify the built-in control program to do what you want. It's intended to control servos which use PWM in the range of 0.5ms to 2.5ms (roughly), but it would be easy enough to disable whatever bounds checking is in the program and modify it to accept more than 2 bytes of PWM width data if you need that kind of pulse width range.