Hmm, what do you mean with "C10 has added a count of one"?..i thot the function [=C10 K1] was purely a comparison, comparing value of C10 to 1 then if true M204 will be true..Does it increment?..Do i get what you try to say?..Kindly correct me
Somewhere in your program something incremented or decremented the value in C10 and when that value became 1(K1) the compare statement became true. Try a search using the Find Device function of GX developer for ALL locations of C10 in your program. You should be able to put the missing pieces of your puzzle together. If not try posting your program here so that we can help you further.