Yokogawa PR300 Power and Energy Meter - Manual (Page 69)

4-8
<Toc> <Ind> <4. PC Link Communication Protocol>
IM 77C01E01-10E
WWR Writes data into D registers on a word-by-word basis
●
Function
This function code writes information into a sequence of contiguous registers on a word-by-
word basis by the specified number of words, starting with a specified register number.
• The number of words to be written at a time is 1 to 64.
• For the format of response in the event of failure, see subsection 4.1.2.
• The command shown below includes the checksum function. When performing
communication without the checksum, do not include the 2-byte checksum element in
the command.
●
Command/Response (for normal operation)
Write information is specified in a 4-digit character string (0000 to FFFF) in
hexadecimal.
ddddn: write data of the specified number of words
ddddn = character string in hexadecimal
n = 1 to 64 words
Number
of Bytes
Command
element
1
STX
2
Station
number
(ST-NO)
5
Register
number
1
Comma
or space
2
Number
of words
(n)
1
Comma
or space
4
dddd1
4
dddd2
4
ddddn
2
01
3
WWR
1
0
…
…
2
Checksum
1
ETX
1
CR
Command (continued)
Number
of Bytes
Response
element
1
STX
2
Station
number
(ST-NO)
2
01
2
OK
2
Checksum
1
ETX
1
CR
●
Example
Write the floating point data “00004120” into the VT ratio (register symbol: VT L and VT H)
and CT ratio (register symbol: CT L and CT H) of the PR300 at station number 01.
The register numbers for VT ratio are D0201 and D0202.
The register numbers for CT ratio are D0203 and D0204.
[Command]
[STX]01010WWRD0201,04,0000412000004120C3[ETX][CR]
“OK” will be returned in response to the command above.
[Response]
[STX]0101OK5C[ETX][CR]
VT ratio: 4-byte floating-point hex data 0000 4120 → (reversed) → Hex 4120 0000 ⇒ Decimal 10
CT ratio: 4-byte floating-point hex data 0000 4120 → (reversed) → Hex 4120 0000 ⇒ Decimal 10
Note: To use the response data as the reading, reverse the order of the upper and lower words.