Uart Interface; Modbus Protocol Over Uart Interface; Modbus Register Map - E+E Elektronik EE895 User Manual

4.2

UART Interface

4.2.1

Modbus Protocol Over UART Interface

Modbus slave address: 0x5F
The interface settings are: Baud rate 9600, 8 Data, No parity, 1 Stop bit (9600 8 N 1)
The slave address and the interface settings are fixed, they cannot be changed by the user.
The EE895 module shall be addressed according to the specification "Modbus over serial line V1.02",
see http://www.modbus.org/docs/Modbus_over_serial_line_V1_02.pdf
Modbus frame description (screenshot taken from the "Modbus over serial line Specification and Imple-
mentation Guide V1.02" mentioned above):
4.3

Modbus Register Map

Following Modbus register map is valid for both, the I
saved as 32 bit floating point values (data type FLOAT) and as 16 bit signed integer values (data type
INTEGER), please refer to Tab. 9 and Tab. 10 below:
FLOAT 32 bit
Parameter
Read register: function code 0x03
Temperature T
Temperature T
Temperature T
CO (average)
2
CO (raw)
2
Pressure p
Pressure p
1) Register number starts from 1
2) Register address starts from 0
Tab. 9 I C and UART Modbus register map for 32 bit floating point values
2
14
C and the UART interface. The measured data is
2
Unit Register number
° C 1003
° F 1005
K 1009
ppm 1061
ppm 1063
mbar 1201
psi 1203
User Manual EE895 Miniature Sensor Module for CO
.
[DEC] Register address
1) 2)
0x3EA
0x3EC
0x3F0
0x424
0x426
0x4B0
0x4B2
[HEX]
, T and p
2