adccommunitymod (AutomationDirect) asked a question.
Created Date: March 21,2018
Created By: z28z34man
**** This post has been imported from our legacy forum. Information in this post may be outdated and links contained in the post may no longer work.****
i am in the process of installing a ViewMarq display on a machine with a 1769-L16ER-BB1B compact logix PLC. The samples in the manual all assume the compact logix PLC has a serial port and this one dose not. I ordered a 1734-485ASC point IO RS485 ASCII module to install and now that i am messing with the program i am finding that it has a 127 character maximum transmit. is it possible to break up the 500 character string to be sent 125 characters at a time. this would have been much simpler and cheaper if i would have ordered a productivity 1000 PLC and just had it grab the info i needed from the compact logix via Ethernet IP
Created Date: March 21,2018
Created by: z28z34man
i am in the process of installing a ViewMarq display on a machine with a 1769-L16ER-BB1B compact logix PLC. The samples in the manual all assume the compact logix PLC has a serial port and this one dose not. I ordered a 1734-485ASC point IO RS485 ASCII module to install and now that i am messing with the program i am finding that it has a 127 character maximum transmit. is it possible to break up the 500 character string to be sent 125 characters at a time.
this would have been much simpler and cheaper if i would have ordered a productivity 1000 PLC and just had it grab the info i needed from the compact logix via Ethernet IP
Created Date: March 21,2018
Created by: jackson
Yes, this is possible. Look at the CLICK example of page 7-7 of the manual. I think the caveat would be that you do the termination code on the last ASCII send (not in the port settings as is possible with some of the AB PLCs).
Created Date: March 22,2018
Created by: z28z34man
Thanks. That's is what I was thinking but wasn't sure. I should have the 1734-485ASC some time tomorrow to do some testing. The AB manual isn't the best for this card so there will be a lot of trial and error.
Created Date: March 22,2018
Created by: kewakl
If you haven't downloaded the viewmarq software, you should -- if only for building valid messages (with formatting codes.)
http://support.automationdirect.com/products/viewmarq.html
Created Date: April 09,2018
Created by: z28z34man
updates for anyone considering a similar project. a couple quarks that threw me for a loop. With a compact logix PLC that uses point IO as local IO has terminals marked FP+ and FP- those need 24 volts on them. The 1734-485ASC needs to be firmware 4.1 or above to work as local IO on a compact logix PLC. And 250 ms was too slow between messages that set up the initial text. 50 ms works great.
I have had this going for almost 2 weeks now and it is working great.