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IQAN Design with MC4X wont allow Frequency/Direction Sensor types (DPCNT)

Ryan Wadewitz 4 weeks ago in IQANdesign updated 4 weeks ago 2

It appears in the manuals that the MC41 can accept a Frequency/Direction sensor type and is allowed in the System Layout area of IQAN Design, but you get an "Error: Property not Available" in the application portion.  I have tried using an event counter with the high speed DINs (C1 Pins 11 and 12).  I have cycle time of the MC41 set to 1ms.  The results are inconsistent at best with error in pulse count up to 25% at approximately 200Hz.  I tried using   PCNT input with the high speed input for direction.  It improved, but is still not accurate as the pulse count seems to double and miss counts on direction change.  Is this a software bug? Is there another work-around?

The MC4x only support quadrature type sensors (two offset frequencies) using the Frequency / Direction inputs.  


In order to support a frequency sensor where a digital state indicates direction, you'll need to use separate frequency and digital inputs and then combine appropriately in the application.

The property is legacy for the XA2.

Edward,

I have tried using a PCNT and a DIN combined in an event counter.  I believe the inaccuracy is do to the pulse count being faster (greater the 1kHZ) than the event counter (cycle time @ 1ms).  The solution seems to miss counts.  Also, the PCNT seems to add a count for rise and fall of each pulse.  On an oscilloscope, the sensor is acting per spec, driving a square wave for each tooth and direction.  The sensor is a ZF SD101201.  How would you combine the 2 channels to improve this phenomenon?