The Main type is a counter that uses up to 6 fast inputs and 2 reflex outputs.
The Main type supports the following counting modes on single phase (1 input) or dual-phase (2 inputs) pulses:
One-shot: In this mode, the counter value register decrements (from a user-defined value) for each pulse applied to the A input until the counter reaches 0.
Modulo-loop: In this mode, the counter repeatedly counts up from 0 to a user-defined modulo value, then returns to 0 and restarts counting. In reverse, the counter counts down from the modulo value to 0, then presets to the modulo value and restarts counting.
Free-large: In this mode, the counter behaves like a full range up and down counter. Can be used with one encoder.
Event Counting: In this mode, the counter accumulates the number of events that are received during a user-configured time base.
Frequency meter: In this mode, the counter measures the frequency of events. Frequency is the number of events per second (Hz).
Period meter: Use the Period meter mode to:
odetermine the duration of an event
odetermine the time between 2 events
oset and measure the execution time for a process
Optional features can be configured depending on the selected mode:
oHardware inputs to operate the counter (enable, preset) or capture the on-going counting value
oUp to 4 thresholds, the values of which can be compared.
oUp to 4 events (1 for each threshold) can be associated with external tasks
oUp to 2 reflex outputs
The maximum frequency admissible on an Expert I/O interface is 100 kHz.
