User manual

Toolbox 32 User Manual 1.47d www.cse-semaphore.com/mykingfisher
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Ladder Logic - Edge Trigger
Caution! After downloading ladder logic, a Positive Edge Trigger or Change block will be TRUE for one
ladder scan if the test bit is TRUE. This can be prevented by also testing the system register flag
#YSYS.ENABLE. Note: a warm start or a power reset will not affect these blocks.
Positive Edge Trigger
Block is true for one ladder scan when the test bit makes an OFF to ON transition (0 to 1). Eg. bit 1 of R1
makes a 0 to 1 transition. As used in the topic Example - Counting Pulses And Starts.
Negative Edge Trigger
Block is true for one ladder scan when the test bit makes an ON to OFF transition (1 to 0). Eg. bit 1 of R1
makes a 1 to 0 transition.
Change Detect
Block is true for one ladder scan when the parameter changes value. The parameter can be a single bit or a
register. Eg. bit 1 of R1 makes a 0 to 1 or a 1 to 0 transition (change of state). When the parameter is a
register, all 16-bits are monitored for change. As used in the topic Example - Rolling Totals Over At Midnight.