MD10C Not working properly. Is it me?

Autonomous Robot, Manual Robot, DC Motor Driver, Stepper Motor Driver, Servo, Multi PWM chip.....

MD10C Not working properly. Is it me?

Postby djthomas1189 » Wed Nov 16, 2011 5:08 am

I am using the MD10C motor driver for a school project and I can't seem to get it to work properly here's what I got going on.
Parts:
Dragon 12 Board (microprocessor I'm using)
2 Variable voltage supplies
MD10C Motor Driver
12V and or 24V brushed DC motors

Setup:
12V from one power supply going into the VIN of the MD10C
12V or 24V from the other power supply (depending on motor wired in) is going in the power input (+ -> +, neg ->neg)
MD10C A and B ports are connected to Motor Leads
MD10C PWM pin connected to PWM pin on Dragon Board (Frequency < 10KHz, with in product spec)
MD10C DIR pin connected to an i/o pin on Dragon Board.
This is how the manual explain how the set up should be.

Results:
When I set the DIR pin to LOW the motor move CW and with full PWM speed control. A port LED lights up.
When I set the DIR pin to HIGH nothing moves.

I did a little test that instead of using a PWM signal I replaced it either Logic HIGH or LOW. Here are the results.

PWM: High(5V)
DIR: Low
Result: LED A lights up, Clockwise motor rotation, The "B" switch will stop motor movement

PWM: High(5V)
DIR: High
Result: A nor B LED light up, No motor movement, the "A" and "B" switch can control CW and CCW motor movement

PWM: Low
DIR: High or Low
Result: A nor B LED, No motor movement, the "A" and "B" switch can control CW and CCW motor movement

It seems there is something wrong with the ability to flip of polarity of the output motor PWM

I also tried the Locked-phase PWM wiring set up. This setup performs as if the polarity of the motors isn't being switched. 50% duty should = no motor movement, I get about 50% CW movement. 25% duty < movement than 50%, 75% duty > 50% duty movement.

I've tested 3 other boards and they all perform the same. I'm at loss, please help
djthomas1189
Greenhorn
 
Posts: 2
Joined: Wed Nov 16, 2011 4:42 am

Re: MD10C Not working properly. Is it me?

Postby djthomas1189 » Wed Nov 16, 2011 5:53 am

I discovered something weird. If anyone can explain this please do.

If I switch the jumper to "PWR" be powered by the motor input voltage and then connect the DIR pin to i/o and the GND a ground, the driver behaves exactly how I want it too.

Why does VIN as the power supply cause the driver to not work as expected?
djthomas1189
Greenhorn
 
Posts: 2
Joined: Wed Nov 16, 2011 4:42 am

Re: MD10C Not working properly. Is it me?

Postby waiweng83 » Wed Nov 16, 2011 9:48 am

Hi,

It seems like the problem lies on the 12V power supply connected to the Vin. Can you please measure what is the voltage on Vin with respect to Gnd?
Please measure the voltage in the condition where the motor driver is not working as intended.

Thanks.
With the power of dream, nothing is impossible...
User avatar
waiweng83
Moderator
 
Posts: 157
Joined: Wed Apr 15, 2009 2:17 pm


Return to Robot Controller

Who is online

Users browsing this forum: No registered users and 4 guests

cron