Preset Function

Overview

The preset function is used to set/reset the counter operation.

The preset function authorizes counting function, synchronization, and start in the following counting modes:

One shot counter: preset and start the counter
Free-large counter: preset and start the counter
Modulo-loop counter: reset and start the counter
Event counting: restart the internal time base at the beginning

NOTE: Sync condition for a Simple HSC type corresponds to the function block input Sync.

Description

This function is used to synchronize the counter depending on the status and the configuration of the optional SYNC physical input and the function block inputs F_Preset and EN_Preset.

This diagram illustrates the Sync conditions of the HSC:

EN_Preset input of the HSC function block

F_Preset input of the HSC function block

SYNC physical input SYNC

The function block output Preset_Flag is set 1 when the Sync Condition is reached.

Either of the following events trigger the capturing of the Sync Condition:

Rising edge of the F_Preset input
Rising edge, falling edge, or rising and falling edge, of the SYNC physical input (if the SYNC input is configured, and the EN_Preset input is TRUE).

Configuration

This procedure describes how to configure a preset function:

Step	Action
1	In the Devices tree, double-click MyController > IO_Bus > Module_x > Counters.
2	Set the value of the Counting function parameter to HSC Main Single Phase or HSC Main Dual Phase.
3	Select the value of the Control inputs > SYNC input > Location parameter.
4	Select the value of the Control inputs > SYNC input > Filter parameter.
5	Select the value of the Control inputs > SYNC input > Preset condition parameter to specify the transition type of the SYNC physical input: SYNC Rising. Rising edge of the SYNC input SYNC Falling. Falling edge of the SYNC input SYNC Both. Both edges of the SYNC input