Rslogix 500 using one shots ons osr osf commands

OSR One Shot Rising – Rungs 3 and 4 use the OSR One Shot Rising bit.  Pressing the Yellow Button once will turn on the Yellow Light.  Pressing the Yellow Button again will turn off the Yellow Light.  The OSR One Shot Rising has two bits.

Storage bit – is used to remember the state of the OSR.  It is very similar to the EN enable bit of a timer and counter and means that instructions preceding the OSR are true. Typically this instruction isn’t addressed in the program.

Output bit – The output bit is set for one scan when the instructions preceding the instruction are true. The timing of this one scan is important to understand.  The bit will be set as true on Rung 3 and stay true until the program comes back around to Rung 3 again then turn off.

OSF One Shot Falling – Rungs 5 and 6 use the OSF One Shot Falling bit.  Pressing the Blue Button does nothing, but releasing the Blue Button will turn on the Blue Light.  Pressing and then releasing the Blue Button again will turn off the Blue Light.  The OSF One Shot Falling has two bits.

Storage bit – is used to remember the state of the OSF.  It is very similar to the EN enable bit of a timer and counter and means that instructions preceding the OSR are true.  Typically this instruction isn’t addressed in the program.  Note that this is IDENTICAL to the OSR.  Only the Output bit functions differently.

Output bit – The output bit is set for one scan when the instructions preceding the instruction are FALSE.