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When using the 140 EHC202 00 High Speed Counter, how do I reset my counter value(s) to zero, or maximum value?

Using the "Parameter" screens the module is configured for its set points,max value
and mode of operation. To reset the count is a simple matter of sending a command
to the first 4x register of the module's I/O map reference. Prior to doing anything you
should be aware of the terminology involving this module.

Reset: Turning off the output coils associated with the card. Reset has nothing to do
with your count values being set to 0 or max value.
Preset: This can be a hardware input or software command. Preset will set your current
count to zero if your counting up, or to max value if your counting down.

To Preset and Enable counters 1 and 2... Send the value 233H to the module.
To Preset and Enable counter 1 only..... Send the value 203H
To Preset and Enable counter 2 only......Send the value 230H

A hardware Preset is accomplished by pulsing the Preset input terminal on the EHC 202 for counter 1
or counter 2.

Follow the above mentioned command with a 300H command, which is the Read Counter command.
If you want to know what the last count was prior to Preset,send a 400H command. This command
will buffer the last count seen by the counters just before the Preset command arrived.

Remember, you can Preset the module with hard wired inputs to the Preset input of each counter or
you can use the software Preset described here. It is permissible to use both methods simultaneously
if you wish. Follow the wiring diagrams in the Quantum Hardware Reference Guide, they are accurate and
should be relied upon for proper module operation.

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