Siemens SIMOCODE pro Function Manual page 101

In the example, the following status information is returned:
● Device ok
● Bus ok
● PLC/PCS ok
● Current flowing ok
● Motor on>
See also Device diagnostics (Page 282) for more information.
The returned bytes contain the bits in the following order:
Byte 1: 0x3C == address 0x1C0F - 0x1C08
Byte 2: 0x08 == address 0x1C17 - 0x1C10
Function codes 03 - Read Holding Register and 04 - Read Input Registers
Function
This function enables the Modbus master system to read registers from the SIMOCODE pro
register memory area.
Functions codes 03 and 04 behave in the same way here and supply an identical feedback
signal. A valid offset from the register memory area is expected as the start address. Up to
125 registers per frame can be read.
Request message frame
Slave address
1 byte
Response message frame
Slave address
1 byte
Example: Reading in of the SIMOCODE pro current measured values from slave number 16.
The current measured values start from offset 0x0807 and comprise 3 registers.
Request message frame
Slave address
1 byte
0x10
Response message frame
Slave address
1 byte
0x10
In the example, the measured values of the current motor current in phases 1, 2 and 3, each
with 100 % (0x0064) of the rated motor current, are returned as the feedback signal.
SIMOCODE pro - Communication
Function Manual, 11/2018, A5E40508495002A/RS-AC/003
Function code Start address
1 byte 2 bytes
Function code Number of bytes
1 byte 1 byte
Function code Start address
1 byte 2 bytes
0x03 0x8007
Function code Number of bytes
1 byte 1 byte
0x03 0x06
Communication
2.3 Modbus communication
Number of registers CRC
2 bytes 2 bytes
Register value CRC
n registers 2 bytes
Number of registers CRC
2 bytes 2 bytes
0x00 0x03 0x ....
Register value CRC
3 registers (6 bytes) 2 bytes
0x0064 0x0064 0x0064 0x ....
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