PLC 2/16 Instruction addressing

[Guest jimnevins]

I have taken on the task of converting a "hard copy" of PLC 2 logic to a new project in RSLogix 500 to a 5/05 processor with identical modules...Im currently trying to learn how the addressing convention works in the old PLC 2 logic and covert it to SLC logic...does anyone have any suggested reading on how to decifer the old logic in PLC 2?

[steve708 0]

Go to www.ab.com to the Manuals Online section. I think they still have PLC-2 manuals there. PLC-2's are pretty simple. The five digit address is "wwwbb" where w means word and b means bit. In a PLC 2/16, words 010-017 would be your outputs for Rack 1, and 110-117 would be your inputs. The first digit is 0 for output and 1 for input. The second digit is the rack number. The third digit is the group number in the rack. The last two digits would be the bit, so "01203" would be terminal 03 of the output card in group 2 of rack 1. Timers and counters start at address 030 and there is no distinction between the two. You can have timer 031 followed by counter 032, then timer 033, etc. The presets are stored in the word 100 octal above, which would be 130, 131, 132, etc. You can use any words for storage bits but you have to make sure not to use the same address as a timer or counter. Just remember everything is octal - no 8's or 9's anywhere.

[Guest jimnevins]

thanks steve, what about the 200's instructions? that doesn't jive with the I/O naming convention...

[Guest Will Harrington]

Keep in mind that the PLC-2/16 uses 2-slot addressing, with the first slot usually being an input card and the 2nd slot being an output card. Your earlier question about items with an address of 200 is an internal bit (an item not mapped to an input or output). I do have (2) PLC-2/16s and the original A-B manual FOR SALE. If you are interested, please email me at... wharring@advancedtech.com