6 Message Communications
6-24
CJ-series DeviceNet Units Operation Manual for NJ-series CPU Unit(W497)
Byte Data Write writes data to any I/O memory area in the memory used for CJ-series Unit in a CPU
Unit with a CJ-series DeviceNet Unit mounted. The write word data is in byte units. The command block
is specified from high to low bytes, as shown in the following diagram.
z Command Block
* A body format of either 8 bits or 16 bits is possible.
z Response Block
z Parameters
Service Code (command, response): 1E Hex is specified for commands. For responses, the high-
est bit will turn ON and 9E 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 to which the data
will be written is specified as shown in the following table.
Note You cannot use Holding Area H512 and its subsequent holding areas, or EM Area Bank D and its subse-
quent banks.
Address L, Address H (command): The address of the first word to which the data will be written
is specified in hexadecimal as shown below.
Address L: The lower 2 digits when the first word address is displayed in 4-digit hexadecimal.
Address H: The higher 2 digits when the first word address is displayed in 4-digit hexadecimal.
Write Data (command): The specified area and write data is returned in order from word H (higher
byte: bits 8 to 15) to word L (lower byte: bits 0 to 7). If an odd number is specified, the last 1 byte of
data will be written to word H.
z Important Points
The actual address L, address H, and number of write data words that can be specified depends on
the type of CPU Unit with CJ-series DeviceNet Unit mounted and the type of memory area. Do not
exceed the boundary of the data areas for the CPU Unit you are using.
Byte Data Write (Service Code: 1E Hex)
Instance ID (Hex) CPU Unit memory area
for write
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
1E 2F
(*) (*)
Address L
Service Code
Address H Word data L
Word data H
Word data L
Write data (200 bytes max.)
Word data H
Service Code
9E