Sharing bits btw two different plc5 processors

I need to setup some bit transfers between two processors, similar to producing and consuming in control logix but I'm dealing with plc5. If it's messaging, where could I find an example of how to set this up. Thanks

the Global Data method is probably the easiest - as long as the two PLC-5 processors are connected together by Data Highway Plus ...

http://www.plctalk.net/qanda/showthread.php?p=376296&postcount=9

note that this will transfer a 16-bit word at a time ... you don't have to use all of the bits ...

Ron, Thanks I'll take a look at that method!

one downside to the Global Data method is that many (most?) technicians aren't familiar with it - so they usually can't figure out where the data is coming from - and what's making it move ...

specifically, there won't be anything in the Ladder Logic code showing how the transfer gets made ...

if that might be a consideration for your system, then post again and we'll cover how to set up an MSG (Message) instruction ... at least that way there'll be a "logic trail" to help track down the data transfer ...

I looked at the global status file in Ch 1A and it is already setup with file N103 as the the global shared file across 4 different processors all using 103. The binary has 103:0/0 thru 103:63/15. I chose one that is not used and toggled from processor while looking at the other and I don't get the handshaking. This is PLC 5, so would I need to create messaging for this? This is on DH also.

Thanks
Rich

not 100% sure what you're saying ... can you post a screen shot?

basic idea: the DH+ network has 64 possible addresses (they're OCTAL numbered) ... each one of those stations has its own independent "mail box" - based on its own particular DH+ node address ... (these are DECIMAL addressed - so you have to be careful relating the OCTAL and the DECIMAL) ...

I chose one that is not used

Click to expand...

chose one "WHAT" ??? ... a "mailbox" ??? ... that might be your problem ... you don't just "choose" one ... the specific mailbox (1 of the 64 possibilities) is determined by the processor's DH+ node number (assigned by DIP switch settings on the PLC-5 processor) ...

anyway ...

once you figure out exactly which "mailbox" is being written to by each particular processor, then the rest should fall into place ...

or just use an MSG command ...