Omron CJ1W-DRM21 Operation Manual page 210

6 Message Communications
Command Block
1C 2F
(*)
Class ID
Service Code
* A body format of either 8 bits or 16 bits is possible.
Response Block
9C
Service Code
Word data H
Parameters
Service Code (command, response): 1C Hex is specified for commands. For responses, the high-
est bit will turn ON and 9C Hex will be returned.
Class ID (command): Always 2F Hex.
Instance ID (command): The type of area in the memory used for CJ-series Unit that will read the
data is specified as shown in the following table.
Instance ID (Hex)
01
03
04
05
08 to 14
Address L, Address H (command): The address of the first word from which to read the data is
specified in hexadecimal as shown below.
Address L: The lower 2 digits when the first word address is given in 4-digit hexadecimal.
Address H: The higher 2 digits when the first word address is given in 4-digit hexadecimal.
No. of Read Bytes (command): The number of bytes of read data is specified in 1-byte (2-digit)
hexadecimal. The range is 01 to C8 Hex (1 to 200 decimal).
No. of Bytes Received (response): The number of bytes received from the destination node
address (remote node) is returned in hexadecimal.
Destination Node Address (response): The node address of the CJ-series DeviceNet Unit that
returned the response is returned in hexadecimal.
Read Data (response): The specified area, word, and byte data is returned in order from word H
(high byte: bits 8 to 15) to word L (low byte: bits 0 to 7). If an odd number is specified for the number
of read bytes, the last 1 byte of data will be read to the high word.
Important Points
The actual address L, address H, and number of read bytes that can be specified depends on the
model of the CPU Unit of the CJ-series DeviceNet Unit and the type of memory area. Do not exceed
the boundary of the data areas for the CPU Unit you are using.
6-22
(*)
Address L No. of bytes read
Instance ID Address H
Word data L Word data L
Word data H
Read data (200 bytes max.)
CPU Unit memory area
for read
CIO
DM
WR
HR
EM, banks 0 to C
CJ-series DeviceNet Units Operation Manual for NJ-series CPU Unit(W497)
Word range
CIO 0000 to CIO 6143
D00000 to D32767
W000 to W511
H000 to H511
En_00000 to En_32767
(n: 0 to C)