Use this function to clear the current counter value. Furthermore, you can acknowledge that the current value is cleared. You can use the clearing feature is available whether the counter is ON or OFF.
To clear the current counter value with 0, turn ON the clear flag under the CH counter input control request in the system variable (#L_ExIOCntInCtrl). The Operation bit will differ depending on the CH to which you allocate the high-speed counter.
#L_ExIOCntInCtrl
Counter input control request
Turn ON the start bit (bit 0) of each CH to clear the counter value.
For variables allocated in [Counter Input Control Response], the watch bit differs depending on which CH you allocate the high-speed counter to, as shown below.
If the start bit of the CH (0 bit) is 1, clear is complete. If it is 0, clear is incomplete.
The following figure shows the flag timing chart for clearing current counter value and completion.
1) Turn on the request flag for the counter value clear to clear the current counter value.
2) Once the current counter value is cleared, the completion flag of the count value clear turns ON.
3) Acknowledge that the completion flag of the counter value clear is ON and turn OFF the request flag for the counter value clear.
4) When the request flag for the counter value clear is recognized as OFF, the completion flag of the counter value clear turns OFF.
When you are using 2-phase settings, arrangement of mapped terminals will differ.
For details about the 2-phase settings, please see the following.
31.5.7 High Speed Counter (2-phase Settings)