Hitachi SJ Series, User Manual

Page: 499 / 786

14-8
Chapter 14 RS485 Communication
14.3.3 Function codes
• Specify functions the inverter executes using function
codes.
Function code
14.3.4 Data
• Transmit the data related to function codes.
• The inverter corresponds to the data formats shown
below among data used in Modbus.
Corresponding function codes are shown below:
• Transmission formats of data vary depending on function
codes.
Function Code Function Max. Data Bytes Handled by
1 Message Max. Number of Data
Handled by 1 Message
01h Reads out the state of coil. 4 32 coils (bitwise)
03h Reads out the content of retention
register. 32 16 registers (in bytes)
05h Writes to coil. 2 1 coil (bitwise)
06h Writes to retention register. 2 1 register (in bytes)
08h Loopback test - -
0Fh Writes to multiple coils. 4 32 coils (bitwise)
10h Writes to multiple retention registers. 32 16 registers (in bytes)
17h Writes / reads out to multiple retention
registers. 32 / 32 16 / 16 registers (in bytes)
Data Name Description
Coil Writable/readable binary data (1 bit long)
Retention register Writable/readable 16 bits long data