SMAX MODBUS®
Request PDU
(in hexadecimal format)
[01][04][00][01][00][01][60][0A]
where:
[01] = Slave address
[04] =
function code
[00][01] = starting address (
parameter, register 2)
[00][01] = number of requested registers
[60][0A] = CRC
The full frame needed to send back the value of the
parameter (register 2) from the Slave having the node address 1 is as
follows:
Response PDU
(in hexadecimal format)
[01][04][02][13][C5][74][53]
where:
[01] = Slave address
[04] =
function code
[02] = number of bytes (2 bytes for each register)
[13][C5] = value of register 2
, 13 C5 hex = 5061
dec
[74][53] = CRC
06 Write Single Register
FC = 06 (06 hex)
This function code is used to WRITE a single holding register in a remote device.
The Request PDU specifies the address of the register to be written. Registers are
addressed starting at zero. Therefore register numbered 1 is addressed as 0.
The normal response is an echo of the request, returned after the register
contents have been written.
For the complete list of registers accessible using
function code please refer to the “7.1.1 Machine data parameters (Holding
registers)” section on page 59.
MAN SMAX MB E 1.2
Modbus® interface
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