Omron CJ1W-DRM21 - Page 210

6 Message Communications
6-22
CJ-series DeviceNet Units Operation Manual for NJ-series CPU Unit(W497)
z Command Block
* A body format of either 8 bits or 16 bits is possible.
z Response Block
z 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.
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.
z 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.
Instance ID (Hex) CPU Unit memory area
for read
Word range
01 CIO CIO 0000 to CIO 6143
03 DM D00000 to D32767
04 WR W000 to W511
05 HR H000 to H511
08 to 14 EM, banks 0 to C En_00000 to En_32767
(n: 0 to C)
Class ID
Instance ID
1C 2F
(*) (*)
Address L
Service Code
Address H
No. of bytes read
9C
Service Code
Word data H
Word data L
Word data H
Word data L
Read data (200 bytes max.)