Parameter access command message structure, Parameter access response message structure, Network communications 3-9 – Yaskawa Profibus-DP Option Card CM061 User Manual
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Network Communications 3-9
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Parameter Access Command Message Structure
Two command, output, functions are available, read parameter data, 03h, and write parameter data, 10h. If no Parameter Access
communications is desired, use 00h as the function code. These function codes are programmed in byte 4 of the 6 word input/output
message. Bytes 5 and 6 contain the address of the parameter to be accessed. Byte 7 contains the number of data bytes to be read from or
written to the drive. Since only one parameter may be accessed at a time, this value must always be set to 2. Bytes 8 and 9 contain the data
to be written to the selected parameter. If the command is to read parameter data, bytes 8 and 9 must be set to 0.
Table 3.10 – 6 Word Input/Output Message Parameter Access Command Messages
Output Data – Parameter Access Command Message (PROFIBUS-DP Master -> Drive)
Byte
Name
Function
4 Function
Code
Parameter Access Command Code (Read data = 03h, Write data = 10h)
5 Starting
Address
MSB
6 Starting
Address
LSB
The first register to be read or written
7
Data Quantity
Bytes of data (2 x Number of parameters to be read or written)
8
Data 1 MSB
9
Data 1 LSB
Value of data to write to the drive parameter Starting Address
10 Reserved
11
Handshaking Register
Synchronizes drive communication with PROFIBUS-DP Master
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Parameter Access Response Message Structure
The standard Parameter Access response structure is described below. In a non-erroneous response, the Function Code, Starting Address
and Data Quantity are identical to the command message. If the command function code is 03h, read data, the data bytes will contain the
values of the requested registers. If the command function code is 10h, write data, the data bytes will contain 0 and should be ignored.
Table 3.11 – 6 Word Input/Output Message Parameter Access Response Structure
Input Data – Parameter Access Response Message (Drive -> PROFIBUS-DP Master )
Byte
Name
Function
4 Function
Code
Parameter Access Response Code (Command code or command code & 80h for error)
5 Starting
Address
MSB
6 Starting
Address
LSB
The first register to be read or written
7
Data Quantity
Bytes of data (2 x Number of parameters to be read or written) (always 2)
8
Data 1 MSB
9
Data 1 LSB
Value of data read from the drive parameter Starting Address
10 Reserved
11
Handshaking Register
Synchronizes drive communication with PROFIBUS-DP Master