Clear Counters Reply Data Format

Clear Counters (6)

The Clear Counters Command sets the counters in the PROFIBUS module to zero.

Clear Counters Command Block – Basic Example

In the following command block, Status is returned in %R251—%R252 (words 8 and 9).

Word	Dec (Hex)		Definition

Word 1	4	(0004)	Length of command Data Block
Word 2	0	(0000)	Always 0 (no-wait mode request)
Word 3	8	(0008)	Memory type of COMMREQ status word (%R)
Word 4	9	(0009)	COMMREQ status word address minus 1 (%R10)
Word 5	0	(0000)	Reserved
Word 6	0	(0000)	Reserved
Word 7	6	(0006)	Clear Counters command number
Word 8	8	(0008)	Memory type to write response (%R)
Word 9	250	(00FA)	Starting Address to write response (response written to %R251)
Word 10	2	(0002)	Maximum size of response area

(Word 7) Command Code: Word 7 specifies the Command code for the COMMREQ to be executed . Clear Counters = 6

(Word 8) Local PLC - Memory Type: Words 8—9 specify the location in the PLC where the response will be written. Valid values for Word 8 are listed below

	Value
Type	Dec	(Hex)	Description

%R	8	(0008)	Register memory (word mode)
%AI	10	(000A)	Analog input memory (word mode)
%AQ	12	(000C)	Analog output memory (word mode)
%I	16	(0010)	Discrete input memory (byte mode)
%Q	18	(0012)	Discrete output memory (byte mode)
%T	20	(0014)	Discrete temporary memory (byte mode)
%M	22 (0016)		Discrete momentary internal memory (byte mode)

(Word 9) Local PLC - Memory Starting Address: Word 9 determines the starting address in the local PLC in which the response is to be written. The value entered is the offset (0-based) from the beginning of PLC memory for the memory type and mode specified in Word 8. This offset will be either in bits, bytes, or words depending on the mode specified (for example, if Word 8=16 and Word 9=2, the starting address will be %I9). Valid ranges of values depend on the PLC’s memory ranges.

(Word 10) Response Memory Size: Words 10 specifies the size of the memory block for the response. The Response Memory Size is 2 words. If the Response Memory Size (word 10 in the Clear Counters command block) is set greater than 2, the COMMREQ will succeed. The unneeded memory locations are not written.