RSLOGIX 500

[MIKE31 0]

HI I like to use FLL instruction and make zero all in the destination file but at the same time I do not want to change one or two bits within destination file but I like to make these selected bits zero somewhere else in the program using clear instruction for example in FLL instruction my source is zero and destination is #N12:0 and length is 4 words but I do not want to make bits 12 and bit 14 to zero at word N12;2 I wonder how can I achieve this Thanks

[Guest Admiral_Ken]

Have a look at the masked move instruction. Ken

[Snerkel 0]

Create a rung, double click it and paste the following into it. SOR XIC N12:2/12 OTE B3:0/0 EOR SOR XIC N12:2/14 OTE B3:0/1 EOR SOR FLL 0 #N12:0 4 EOR SOR XIC B3:0/0 OTE N12:2/12 EOR SOR XIC B3:0/1 OTE N12:2/14 EOR This uses B3:0/0 & B3:0/1 as temporary holding registers, then FLL zeros N12, then holding registers set the N12:2 bit back as they were. Change the B3 bits to something suitable.

[Guest Guest_mike31]

please explain what are the SOR and EOR Thanks

[loosewire 0]

Look to me like it means: SOR - Start Of Rung EOR - End Of Rung

[Guest Guest_mike31]

HI I think you right my friend . Many thanks mike31

[Snerkel 0]

loosewire is correct The text I posted can be pasted directly into RSlogix and it will create the rungs and instructions. When you get slick with RSlogix it gets easier/quicker to create some intructions by creating a rung then just typing in the instructions you require. See ASCII Editing in RSlogix help. Tip:- this format is the way you can auto generate ladder using for instance Excel

[MIKE31 0]

HI SNERKEL When n12:2/12 is true then b3;0/0 is true but when FLL istruction becomes active surely all output and input become false . Am I right or missing the point Thanks MIKE31

[Snerkel 0]

Ladder logic is actioned from top to bottom, then your IO is read, then cycle starts again (simplified version ) remember this and you won't go far wrong. Rung 1 If N12:2/12 is ON then B3:0/0 gets turned ON Rung 2 If N12:2/14 is ON then B3:0/1 gets turned ON Rung 3 Clear N12 to zero (B3:0/0 & B3:0/1 haven't been told to change state so don't) Rung 4 If B3:0/0 is ON then N12:2/12 gets turned ON Rung 5 If B3:0/1 is ON then N12:2/14 gets turned ON The rung order is everything, any other order wouldn't work. Edited 17 May 2004 by Snerkel