Omron CJ Series Operation Manual page 225

MSAC1_Read Service
The PROFIBUS DP-V1 MSAC1_Read service allows a PROFIBUS DP-V1 Master Unit to read (param-
eter) data acyclically from a PROFIBUS DP-V1 slave device, which is allocated to that Master unit.
The figures below show the command and response message formats.
 Command Format
 Response Format
Upon normal completion of the MSAC1_Read command service two types of response frames can
be returned:
• A normal data response frame containing the requested data.
• A normal response frame containing PROFIBUS error codes, indicating that the PROFIBUS
service was not completed correctly, although the message was completed normally.
Both response frames are shown below.
 Parameters
Destination address (Command, Response)
The address of the device on the PROFIBUS network, to which the PROFIBUS message will be
sent. The valid address range is 0 to 7E (Hex). The most significant byte in the Response Format is
set to 00.
Device Service Access Point (Command)
The Device Service Access Point for the MSAC1_Read PROFIBUS service must be set to 33 (Hex).
CJ-series PROFIBUS Master Unit Operation Manual for NJ-series CPU Unit (W509)
28 09 33 00
Function
Command
code
code
Device
address
Device Service
Access Point
28 09 00
Response Function
Command
code code code
28 09 00
Command Response Function
code code code
6 Message Communications
5E
Data length
(bytes)
Slot
number
Index number
5E
Actual data Data
length read
(bytes)
DE
Error Error
decode code 2
Error
code 1
6
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