OMRON - SHIFT REGISTER

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I have enabled the hardware Interrupt on input 0 of an Omron CJ1M-CPU21and tested it is working correctly. I need a left direction shift register of at least 10 words long that is incremented by this interrupt. I'll be darned if I can get this to work within the interrupt, have tried with a single SFT[010] instruction as well as multiple NSSL[582] instructions. I suspect that because these instructions require an OFF to ON transition that this condition is NOT evaluated within the interrupt. Any suggestions how to make this work?

[Jay Anthony 118]

Use always on with SFTR.

[jeenjang 0]

i think SFTR works the same as SFT if reverse shift is not needed

[BobB 58]

Correct.

[Jay Anthony 118]

Not so correct.... SFT must have a leading edge transition on the shift input. SFTR shifts one bit per scan as long as the shift input is on.

[BobB 58]

Sorry about that. Getting old and forgetful. Normally use a DIFU from a bit or something to shift, or a self resetting timer.

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Forgot to say thnks! Worked great.