Read From Variable Area - Omron E5AR-T User Manual

7.5 Read from Variable Area

Read from a variable area by setting the required data in the following command frame.
Command
Response
Command Frame
Slave Function Read start Number of
address code address elements
H'03
1 1 2
Data name
Specify the unit number of the E5AR-T/ER-T. Set in
Slave address
hexadecimal from H'01 to H'63 (1 to 99).
The function code for Read from Variable Area com-
Function code
mand is H'03.
Specify the address of the set value to read. For more
Read start
information on addresses, refer to Appendix Setting
address
Lists (P. A-6).
Specify the number of set values to read times 2 for the
number of elements. The setting range is H'0002 to
Number of
H'006A (2 to 106).
elements
Example: If the number of set values sets is 2, specify
The check code calculated based on the values from the
slave address through the end of the data. For the calcu-
CRC-16
lation method, refer to Example of CRC-16 Calculation
in 7.2 Frames (P. 7-4).
Response Frame
Slave Function Byte Read data
address code count Data 1
Most significant Least significant
H'03
1 1 1 Number of elements 2 bytes
Data n
Most significant Least significant
Data name
Slave address The value from the command frame is returned here.
The received function code is returned here.
In an error response frame, "H'80" is added to the
received function code to indicate that it is an error
Function code
response.
Example: Received function code = H'03
Byte count Number of bytes of data that were read.
Read data The set value that was read.
This is the check code calculated from the slave address
through the end of the data. For the calculation method,
CRC-16
refer to Example of CRC-16 Calculation in 7.2 Frames
(P. 7-4).

7.5 Read from Variable Area

CRC-16
2 2
Description
H'0004.
Data 1
Data n CRC-16
2
Description
Function code in error response frame = H'83
7-11