Host Engineering Forum

General Category => DirectSOFT => Topic started by: mikep on July 28, 2008, 12:08:53 PM

Title: Passing a variable to a MDRMW Drum
Post by: mikep on July 28, 2008, 12:08:53 PM

I am just starting out.
How do you pass a variable to a MDRMW Drum?
I am tying to do this from a panel.

Title: Re: Passing a variable to a MDRMW Drum
Post by: Controls Guy on July 28, 2008, 12:44:09 PM

What part of the drum are you trying to write to (force a value into the step pointer, alter the mask, redirect the output word, etc.)?

Title: Re: Passing a variable to a MDRMW Drum
Post by: mikep on July 28, 2008, 01:19:09 PM

I already wrote a program that will use the start switch on the front panel to begin the drum routine and it works.
So then,
I added a numeric keypad to my control panel and wish to send the number from the panel to the drum to change the time.
I am really very new to this and my knowledge is poor.
Thank You
 

Title: Re: Passing a variable to a MDRMW Drum
Post by: Controls Guy on July 28, 2008, 01:49:08 PM

By "time" I assume you're trying to change the time counts for a certain step, or maybe the count resolution in 10ms increments.  You can't do this by writing directly to the drum as those positions will only accept a constant input.

What I sometimes like to do with drums is to make the events control relays, then I can write more complex logic outside the drum that turns on the control relay.  This outside logic can include anything you can program in ladder.  Timers, counters, one shots, knock yourself out.  Then you can use a V-Memory register as the setpoint for one of these normal external timers, and write to that.

Title: Re: Passing a variable to a MDRMW Drum
Post by: mikep on July 28, 2008, 02:37:05 PM

Thanks for the help.
I was trying to do something that is not possible.
At least I can try another aproach.
MikeP