5 overview of profibus dp communication, Execu ting communi cat ion – KEYENCE DL-PD1 User Manual

Page 49

Advertising
background image

3-5

Overview of PROFIBUS DP Communication

3-25

- PROFIBUS DP Compatible Network Unit DL-PD1 User's Manual (GT2) -

Execu

ting Communi

cat
ion

3

Reading comparator values (P.V. values) from sensor amplifiers

Comparator values (P.V. values) can be read only in the monitor mode. They cannot be
read in the I/O mode.

"Operation mode of DL-PD1" (page 3-6)

Example of reading the comparator value (P.V. value) from the sensor
amplifier

This example shows how to read the comparator values (P.V. values) from the sensor
amplifiers ID01, ID02, and ID03.

(1) When the comparator value of a sensor amplifier is updated, the value of the input

octet is also updated via cyclic communication.
If the comparator value is correct, the parameter range is -199.9999 to +199.9999.
If the comparator value is over range, under range, or invalid, the previous value is
retained without updating the comparator value. To confirm whether the current
value is correct, use the comparator value property.

(2) The comparator value invalid, comparator value over range, or comparator value

under range is entered.
If the comparator value of a sensor amplifier is "invalid", "over", or "under", the bit
corresponding to the ID number of that sensor amplifier flips to 1.

(1)

Master

Comparator value under range

Input octet 3/10/17 Bit 3 of Slot 1/2/3

Comparator value of ID 01

1234

4567

6789

Input octet 5 to 8 (DEX) of Slot 1

Comparator value of ID 02

2345

5678

7890

Input octet 12 to 15 (DEX) of Slot 2

Comparator value of ID 03

3456

8901

Input octet 19 to 22 (DEX) of Slot 3

Sensor amplifier

Comparator value of ID 01

1234

4567

6789

Comparator value of ID 02

2345

5678

7890

Comparator value of ID 03

3456

8901

Comparator value over range

Input octet 3/10/17 Bit 2 of Slot 1/2/3

Comparator value invalid

Input octet 3/10/17 Bit 1 of Slot 1/2/3

1

1

1

0

0

0

(2)

(2)

(2)

Advertising