My company has recently done some upgrades on a machine with a flexlogix processor. We have always been able to go online (DF-1 rs232)to this processor and complete online edits etc. However, now even though I can see it in RS linx, I am unable to go online or even download to it. When attempting to go online I get a communication error telling me to check path in RS-who. I do this and can see processor fine?
When I cleared processor memory (processor power off, battery out) and downloaded to the blank processor I was able to go online when prompted at the end of the download and work online happily. All was well I thought until I attempted to go offline. Got strange error message telling me communications were lost and I could not go-offline, it then proceeded to go offline! Tried to get back online, same message as before telling me to check path in RS-who?????
This got me thinking. Has the extra code that has been added to this machine taken it too close to the memory limitations? Does going online/offline use memory? Do I have to leave more unused memory. Last time I was online there were 105,000bytes used and 2,000 unused. (controller properties panel info, I thought it was a 64K processor so I don't know how these numbers work?)
Any help/links would be greatly appreciated

http://www.ab.com/silver/flexlogix.html



1794-L33 Flexlogix gone to siver series

Hello,

the fact is that a 1794-L33 has 64k of memory for the PLC program.
The left memory until 105k is for the communication between PLC, comm for going online with PC.

So I think that you are at the memory limit of the FlexLogix.
Try to upgrade your PLC to the 1794-L34 ( 512K ) or reduce your plc program.

Bye

Thankyou for your replies. Yes memory was the problem. We could not reduce program size (in fact, we were have increased it now) so we upgraded to L34 processor. Running fine now. No problems getting online or doing online edits etc