Sharing large data between CLX processors via backplane

Hey guys, I'm hoping for some help here. Normally my machines are small enough that one L62 can handle the load with average cycle times around 70ms. Now I'm doing a larger machine which is going to about double the scan time, so I am separating the logic between two L62s.

My question is, what is the best way to share large amounts of data between the processors, both writing and reading?

I have for example recipes that are upwards of 3000 DINTs, software buses, global interfaces, etc. Not to mention diagnosis information for a global messaging system. Just that structure contains 43,000 DINTs.

Produced/consumed tags, using the CIP protocol are limited to 458 bytes. So that doesn't help much unless I write a handshake to shovel a bunch of data over. That seems tedious, and may be too slow anyway. Not to mention that the tags cannot be directly written from both processors.

The two L62s will be sitting in the same rack, utilizing the same backplane. What are my best options for communicating in large volumes, and ideally writing to the controller tags of one processor from the second processor?

Why not use a L7X processor and it has almost twice the scan time and supports twice the connections 500 vs 250.

Or produce and consume several UDT's

L73,L74, or L75 take your pick. 2x the CPU cycles and TONS of memory. Use one not two.

If you must have two CPU's then I would message large amounts of data like that. Connected messages will be blazing fast across the backplane. I would also carefully consider the rate at which you actually need the data. Only move it as often as you need be it event driven or cyclic. It is unlikely that ALL of that data needs to move continuously.

Actually as I think about it, even if you DO need two use L7x processors. L6x is going obsolete as we speak. There is no good reason for L6x at this point.

RSL

L6x may be going obselete, I don't know. My company likes to save money though, and prefers to use the L6x series if at all possible.

I have figured out though, that I will go with an L72 for the main logic, but I still need an L62S to handle the safety task. What a waste of the rest of that L62S...the safety task only needs like 6 ms.

You say your company likes to save money but you're awfully anxious to shell out money for a 2nd processor & safety partner; two L62 safety processors (both with safety partners) will definitely be more than a single L7x safety processor & safety partner.

L62S with LSP is $11,857 USD list

L63S with LSP is $15,332 USD list

L73S with LSP is $15,247 USD list

2 x L62S is $8467 more than a L73S

I'd advice getting your local RA engineering support involved to help you configure the system for your needs. This much money involved warrants it.

Well, we haven't yet released the L7x series for safety programming. That's not up to me. But I understand your point. I am looking forward to the days when I can just use the L7xS series.

What I didn't realize however, is how affordable the new line is.

L7 safety is out now. You can purchase them.