6-21
6 Message Communications
CJ-series DeviceNet Units Operation Manual for NJ-series CPU Unit(W497)
6-3 Receiving Explicit Messages
6
6-3-1 List of PLC Object Services
This PLC Object service reads detailed status (operation status, operating mode) from the CPU
Unit.
z Command Block
Note A body format of either 8 bits or 16 bits is possible.
z Response Block
z Parameters
Service Code (command, response): 40 Hex is specified for commands. For responses, the high-
est bit will turn ON and C0 Hex will be returned.
Class ID (command): Always 2F Hex.
Instance ID (command): Always 00 Hex.
Read Data (response): The read data is given in the following table. The data is returned after the
service code in the order shown in the table (high to low).
• Operation status: Returns the operation status of the CPU Unit in 1-byte (2-digit) hexadecimal.
00 Hex: "Stop" Mode, 01 Hex: "Run" Mode
• Operating mode: Returns the operating mode of the CPU Unit in 1-byte (2-digit) hexadecimal.
00 Hex: "Program" Mode, 04 Hex: "Run" Mode
Byte Data Read reads any I/O memory area data in the memory used for CJ-series Unit in a CPU Unit
with a CJ-series DeviceNet Unit mounted. The read word data is in byte units. The response block is
returned from high to low bytes.
CPU Unit Status Read (Service Code: 40 Hex)
Operation Status
RUN mode
00 Hex
00 Hex
00 Hex
00 Hex
00 Hex
00 Hex
00 Hex
00 Hex
ASCII with 20 hex (space) in 16 bytes
Byte Data Read (Service Code: 1C Hex)
Class ID
Instance ID
40 2F
(*)
00
(*)
Service Code
C0
Service Code
Detailed status
To Next Page
Loading...
