Produced and consumed bits with GE RX3i controllers

Hi all,

I am making some modifications to a system, PLCs are GE RX3i CPE305s. Until now comms between the PLCs (Ethernet Global Data) has been integers and floats, but now a customer request will result in me needing to send six %M bits from one controller to another. According to what I found in InfoViewer (I'm running Proficy Machine Edition 8.6, FYI), BOOL variables are only supported in arrays with a length of 8n (where n=1,2,3, etc). OK, that makes sense in theory, I just wanted to confirm that if I'm trying to produce/consume all I'll need to do is at the first bit address (%M441 in this case), and I can safely assume that %M441-%M449 will actually be sent with the single line in the Produced/Consumed Exchanges table?

Thanks for any help!

Your starting address for the %M bits must be on a byte boundary. That is, the address must have a remainder of 1 when divided by 8. In your example 441 divided by eight has a remainder of 1 so it is a valid starting address. %M442, %M443, %M444, %M445, %M446, and %M447 are not valid starting addresses.

Sorry for the late reply, Steve your info was very helpful! I've dealt with that bit offset you mentioned in other controllers like Scadapacks, so the concept wasn't foreign but I wasn't aware the GE controllers did it so thanks for the heads up. I was able to get things working perfectly with no issues which was great. Thanks again!