Function 04: Read Input Registers; Table 5.4 Read Input Registers Packet Structure - RLE Technologies LD5200 User Manual

5.4.2 Function 04: Read Input Registers

To read the LD5200 input values, the master must send a Read Input Registers request packet.
The Read Input Registers request packet specifies a start register and the number of registers
to read. The start register is numbered from zero (30001 = zero, 30002 = one, etc).
Read Registers Request Packet
Slave Address (1 byte)
04 (Function code) (1 byte)
Start Register (2 bytes)
# of registers to read (2 bytes)
Crc Checksum (2 bytes)
Table 5.4
rletech.com
Read Input Registers Packet Structure
LD5200 User Guide
Read Registers Response Packet
Slave Address (1 byte)
04 (Function code) (1 byte)
Byte count (1 byte)
First register (2 bytes)
Second register (2 bytes)
...
Crc Checksum (2 bytes)
5 Modbus Communication
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