Yokogawa PR300 Power and Energy Meter - Manual (Page 89)

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IM 77C01E01-10E
5.2 Message and Response
Function codes are command words used by the higher-level device to obtain the D
registers information of PR300.
Table 5.3 Function Codes
Code Function Description
03
06
08
16
Reads data from multiple D registers.
Writes data into D register.
Performs loop back test.
Writes data into multiple D registers.
Capable of reading data from a maximum of 64 successive
D registers between D0001 and D0400.
Capable of writing data into one D register between D0001
and D0400.
Used when checking communication wiring.
Capable of writing data into a maximum of 32 successive
registers between D0001 and D0400.
• The write function codes cannot be written into read-only or user-prohibited D regis-
ters.
• Broadcast addressing is possible with function codes 06 and 16 only. (Also in this
case, cannot be written into read-only or user-prohibited D registers.)