It gets better... more motor interfacing ?''s...
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-Use the easily available PWM coprocessors for each and every
> instance of PWM motor control. Probably would be more expensive
> than I want, plus require board space which don’t want to allocate
> So? Program a processor to do multiple PWM output with a serial
> interface.
> Even better? Make the microprocessor handle motor control (i.e.
> interface with L293D(s)). For each motor unit on the chip,
> simply have 1 PWM out and two outputs for the motor driver chip inputs.
> And the best? Program the micro to accept serial commands. Put
> the motor drivers on a circuit board. Have simple header pins
> for each motor.
>
> AL WILLIAMS, might you be able to develop something like this?
>
Hi Brandon,
Well, I'm not sure I got the particulars, but we have two devices you might
find interesting. First the PAK-V uses a single serial pin and sets 8 PWM
channels. So you can set speed for 8 motors with 1 Stamp pin. Some people
drive these from a PC even. Unlike some PWM chips, all 8 channels run all
the time (unless you disable them). You can change at any time and there is
no adverse reaction on the output (in other words, the output doesn't stop
while you adjust it).
Also, our newest PAK, the PAK-VIII can generate pulse trains. You can use
this to generate PWM or repeating pulses (e.g., for servo control).
I suspect the PAK-V would really do what you want. You can also "jam" a
PAK-V pin low, or hi-z. So with a pull up resistor you can set pins low or
high as you wish. So you could use 4 pins as "digital" outputs for motor
control for 2 motors and 2 pins for PWM. This gives you 2 spare pins (maybe
a control and PWM for a unidirectional motor?). All with one Stamp pin.
I'm not sure if this is exactly what you had in mind, but it seems like it
would be adaptable. If you can shed a little light on what else you want,
let me know.
Regards,
Al Williams
AWC
* Expand your Stamp I/O: http://www.al-williams.com/awce/pak3.htm
> instance of PWM motor control. Probably would be more expensive
> than I want, plus require board space which don’t want to allocate
> So? Program a processor to do multiple PWM output with a serial
> interface.
> Even better? Make the microprocessor handle motor control (i.e.
> interface with L293D(s)). For each motor unit on the chip,
> simply have 1 PWM out and two outputs for the motor driver chip inputs.
> And the best? Program the micro to accept serial commands. Put
> the motor drivers on a circuit board. Have simple header pins
> for each motor.
>
> AL WILLIAMS, might you be able to develop something like this?
>
Hi Brandon,
Well, I'm not sure I got the particulars, but we have two devices you might
find interesting. First the PAK-V uses a single serial pin and sets 8 PWM
channels. So you can set speed for 8 motors with 1 Stamp pin. Some people
drive these from a PC even. Unlike some PWM chips, all 8 channels run all
the time (unless you disable them). You can change at any time and there is
no adverse reaction on the output (in other words, the output doesn't stop
while you adjust it).
Also, our newest PAK, the PAK-VIII can generate pulse trains. You can use
this to generate PWM or repeating pulses (e.g., for servo control).
I suspect the PAK-V would really do what you want. You can also "jam" a
PAK-V pin low, or hi-z. So with a pull up resistor you can set pins low or
high as you wish. So you could use 4 pins as "digital" outputs for motor
control for 2 motors and 2 pins for PWM. This gives you 2 spare pins (maybe
a control and PWM for a unidirectional motor?). All with one Stamp pin.
I'm not sure if this is exactly what you had in mind, but it seems like it
would be adaptable. If you can shed a little light on what else you want,
let me know.
Regards,
Al Williams
AWC
* Expand your Stamp I/O: http://www.al-williams.com/awce/pak3.htm