🚀 go-pugleaf

  The robotics application I'm constructing (which will probably be using the
miniboard) needs to control a lot of motors.  I'll only need one speed, however.
I'll also need forward/backward control.  I'm thinking of a modification add-on
board that will permit each of the miniboard's 4 motor ports to control 16!!!
motors (for a total of 64 motors per miniboard). I would appreciate any net
feedback/comments/suggestions/etc.. that anyone may have.

Here's what I'd like to do:

  At the moment, each of the motors uses a "control" register to control that
motor's direction and speed.  The register is divided in half.. 4 bits to
control forward direction/speed and 4 bits for backward direction/speed.
This gives us 16 speeds forward and 16 speeds backward.

  The miniboard actually sends current (or no current) to the motor in pulses..
If you think of a "time segment" as being divided into 16 units, then the
motor will receive power (or not receive power) for each of the 16 units.
What I'd like to do is feed the motor control leads into another circuit
board that "counts" the number of pulses over 16 time units and selects
the appropriate motor based on how many pulses were received.  The direction
can be selected the same as before (ie: high/low set of control register bits).

  I also don't want the selected motors to operate continuously.  Instead, I'd
like them to only work for about 1/4 to 1/2 a second in the selected direction.
Continuous operation of a motor would be achieved (simulated, actually) by
multiple "enable" commands from the controlling computer (a Sun Sparcstation,
in my case).

  An obvious drawback to the approach I'm considering is that for each bank of
16 motors, only 1 of the motors will be "activated" at a time.  For me, though,
I don't think that this will present too much of a problem as I'll have a
network of 4 miniboards (256 motors total!!) and will only need to control 16
of them at any one time.

  Since my forte' is programming (as opposed to circuit design) I'd really
appreciate any help that can be offered in either creating an add-on board
for the miniboard to accomplish this OR to somehow modify the miniboard itself..


--
Lee Hounshell - (510) 823-2432
tlhouns@srv.pacbell.com
Alchemical Engineer and Virtual Realist