SFC Programming

[GerryB55 0]

Hi I am writing a program using SFC on a Q02 PLC. Under certain conditions the program goes to Step 0 of the block. I need a command for use in this Step which will ensure that ALL other steps in the block are reset. On the FX etc I would use the ZRST function. Any ideas please?

[Guest Ted Vaughn]

Gerry, I may not be much help since I'm not familiar with the Q02 plc, but I have simulated the ZRST command in an A series plc using the FMOV command although it's been a while. Hope this is correct. Example [fmov k0 d100 k50] this should set d100-d149 to 0. Look to see if the Q02 plc has this function. Ted

[tmu 1]

Gerry, you migh know that in ladder!! format you can reset memories using mov k0 k4m0. Resets 4*times 4bit =16bit starting from m0. Dmov k0 k8m0 also possible (32-bits). This is all I know about SFC: http://www.mitsubishi-automation.de/produk...load/130023.pdf Sorry, Tmu

[waynes 8]

Hi GerryB55, Did the manual on the PID command help? I have posted the manual here. Good luck, and enjoy! QCPU_Prog_Man__SFC__SH_080041_C.pdf

[Guest fae-san]

There is no need to reset NORMAL steps in SFC in the Q02. Steps automatically reset when you transition out of them. There are two operation hold steps that will allow you to keep a step active within an active block. The steps are; Operation hold Without transition check [sE] and with Operation Hold with transition check [sT]. These steps can be reset with the reset step [R]. You can also clear an entire block from memory by setting the block information a: Block Start/End bit. This bit will be active when the block is active and if you turn it off that will clear the block from memory. Good luck with your SFC programming.

[GerryB55 0]

Problem solved: I wanted to goto step 0 from within a step not by a transistion, mainly to keep the SFC diagram smaller and neat. The command SCHG K#, where # is the step to goto, in a step goes to the step AND deactivates that step. Thanks for all advice.

[mikeb 1]

Hi, I don't know about SFC but to reset a block of bits use BKRST. ie BKRST MO K8 this would reset M0 to M7