Omron FQM1-CM001 Pulse Inputs, Section, Counter Operation Numeric Ranges, Circular Counter

Pulse Inputs	Section 7-5
Increment/Decrement Pulse Inputs	Pulse + Direction Inputs

Encoder	Encoder
Input A	Input A
(UP input)	(Pulse input)

Encoder						Encoder
Input B						Input B
(DOWN input)						(Direction input)
1	2	3	2		1	1	2	3	2	1
	Increment			Decrement			Increment		Decrement

Counter Operation (Numeric Ranges)

The following two counter operations are available for high-speed counters 1 and 2, with the specified counting ranges.

Circular Counter

With a Circular Counter, the circular maximum count can be set in the System Setup, and when the count is incremented beyond this maximum value, it returns to zero. The count never becomes negative. Similarly, if the count is decremented from 0, it returns to the maximum value.

The number of points on the circular is determined by setting the maximum value (i.e., the circular maximum value), which can be set between 1 and FFFF FFFF hex.

Linear Counter

With a Linear Counter, the count range is always 8000 0000 to 7FFF FFFF hex. If the count decrements below 8000 0000 hex, an underflow is gener- ated, and if it increments above 7FFF FFFF hex, an overflow is generated.

Circular Counter Linear Counter

Circular maximum value

0

Decrement

80000000 hex	0	7FFFFFFF hex
Increment
Underflow			Overflow

	If an overflow occurs, the PV of the count will remain at 7FFF FFFF hex, and if
	an underflow occurs, it will remain at 8000 0000 hex. In either case, counting
	will stop and the PV Overflow/Underflow Flag shown below will turn ON to
	indicate the underflow or overflow.
	• High-speed counter 1: A608.01
	• High-speed counter 2: A609.01
Note	The high-speed counter PVs are refreshed during the Motion Control Mod-
	ule’s I/O refresh.
	When restarting the counting operation, toggle (turn OFF and then ON) the
	corresponding counter’s Reset Bit. (A610.01 is the Reset Bit for high-speed
	counter 1 and A611.01 is the Reset Bit for high-speed counter 2.)
Reset Methods	The following two methods can be set to determine the timing at which the PV
	of the counter is reset (i.e., set to 0):
	• Phase-Z signal and software reset
	• Software reset

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