Author Topic: A great new stepper command for wish list  (Read 11627 times)

cch1955

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A great new stepper command for wish list
« on: October 29, 2012, 01:21:41 PM »
I have used the stepper inder on numerous applications. The boards work very well.

It would be very helpful to have a MOVEHOLD command. The command would cause an executing STEPMOVE to decelerate to a stop and hold at zero speed until commanded (input goes high) causing the motor to ramp back up and complete the STEPMOVE command.

Thanks for the great products.

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Re:A great new stepper command for wish list
« Reply #1 on: October 30, 2012, 08:57:49 AM »
Thank you for your feedback and comments. We are glad you have good experience using the PLC stepper motor. We will forward your suggestion to the development team for consideration.

You may want to consider when a HOLD input is ON, you run a custom function using the STEPSPEED command to decelerate the stepper motor while it is moving and STEPSTOP to stop the stepper, and when the HOLD input is removed you can compute the left over number of pulses that you need to STEPMOVE again to complete the original STEPMOVE  

= total number of steps - STEPCOUNT(1)

STEPCOUNT(n) gives you the number of pulses that the stepper has already travelled on channel #n in the last STEPMOVE so the balance steps can be computed from the difference between the target count and STEPCOUNT(n).  
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cch1955

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Re:A great new stepper command for wish list
« Reply #2 on: October 30, 2012, 10:13:07 AM »
I understand the work around you propose. It is very similar to what I have created to handle the situation with the current software. I works, but requires much more devlopment.

The reason I request this new feature is to simplify what the programmer must do to accomodate a mid STEPMOVE hold requirment. The proposed STEPHOLD command is easily understood and implimented.

Thank you for your consideration.