Internet PLC Forum

General => Technical support => Topic started by: Joel Moore on May 11, 2004, 05:24:54 AM

Title: Writing Single Digital Output
Post by: Joel Moore on May 11, 2004, 05:24:54 AM

I noticed there is a potential issue with the Write Outputs command "WO" when using Host Communications.  If any outputs are supposed to be controlled locally by the PLC then sending a "WO" command can override that control.  One example where this is a problem is when using a stepper motor.  The direction output gets "confused".

So am I right in determining that the only way to remotely control individual outputs rather than entire banks is to use the MODBUS protocol?  

Title: Re:Writing Single Digital Output
Post by: support on May 11, 2004, 10:01:10 AM

On T100MD+ PLC with firmware version r47, we are supporting a new command "Wbnnnnxx" which allows you to turn on any individual I/O bit. These new commands are available in the upcoming T100MD+ User Manual to be printed soon.  A soft copy can be downloaded from:

http://www.tri-plc.com/T100MD-UM.PDF

Check page 4-16 for the description of the "Wbnnnnxx" command. You can also use OMRON host link commands for reading/writing of multiple I/O registers or Data memory. These are mentioned in page 4-20.

Title: Re: Writing Single Digital Output
Post by: Joel Moore on May 11, 2004, 11:30:55 AM

How timely  ;D   And it looks like I'm running r47.

Thanks.