PLC and safety
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LDmicro Forum - PLC and safety
LDmicro Forum - set-reset
Classic PLC scan cycle is:
LDmicro has no "Image register" to hold the inputs/outputs state. All input Contacts and output Coils refer directly to MCU pins.
In this example X1 is read twice per PLC cycle, also Y1 is written twice per PLC cycle.
Also, port A copied to port B twice per PLC cycle.
This architecture has some advantages:
- short pulses inside the PLC cycle are allowed.
Some disadvantages present:
- TODO Please send LD examples to LDmicro.GitHub@gmail.com
You can use Classic PLC scan cycle style with LDmicro:
RS or SR trigger priority (by DanielH)
Thanks to Zdenek Hajek, DanielH.
Any additions are welcome LDmicro.GitHub@gmail.com