3
FLOAT (read register):
Function code /
Register number
1)
[Dec]
Register address
2)
[HEX]
Parameter
name
31003
0x03EA
Temperature [°C]
31005
0x03EC
Temperature [°F]
31041
0x0410
Airflow
[m/s]
31043
0x0412
Airflow
[ft/min]
SHORT (read register)
3)
:
Function code /
Register number
1)
[Dec]
Register address
2)
[HEX]
Parameter
name
34002
0x0FA1
Temperature*
[°C]
34003
0x0FA2
Temperature** [°F]
34021
0x0FB4
Airflow*
[m/s]
34022
0x0FB5
Airflow***
[ft/min]
* Values are stored with the scale 1:100 (e.g.: 2550 is equivalent to 25.5 °C)
** Values are stored with the scale 1:50 (e.g.: 2550 is equivalent to 51 °F)
*** Values are stored with the scale 1:1
INFO (read register):
Function code /
Register number
1)
[Dec]
Register address
2)
[HEX]
Parameter
name
30001
0x00
Serial number (as ASCII)
30009
0x08
Firmware version
INTEGER (write register):
Function code /
Register number
1)
[Dec]
Register address
2)
[HEX]
Parameter
name
60001
0x00
Slave-ID* (modbus address)
60002
0x01
Modbus protocol settings
3)
* If the ID is set via DIP-Switch the response will be NAK.
Please see PICS (Product Implementation Conformance Statement) - available on
www.epluse.com/EE660
BACnet Setup
Modbus Setup
1) Register number starts from 1
2) Register number starts from 0
3) For Modbus protocol setting please see Application Note Modbus (www.epluse.com)
MODBUS RTU EXAMPLE
Example of MODBUS RTU command for reading the temperature (float value) T = 26,652524 °C from the register 0x03EA
Device EE660; slave ID 65
Reference document, chapter 6.3: http://www.modbus.org/docs/Modbus_Application_Protocol_V1_1b.pdf
Request [Hex]:
41 03 03 EA 00 02 EB 7B
Modbus ID
address
Function
code
Starting
address Hi
Starting
address Lo
No. of
register Hi
No. of
register Lo
CRC
Request [Hex]:
41
03
03
EA
00
02
EB
7B
Response [Hex]: 41 03 04 38 5F 41 D5 0A E3
Modbus ID
address
Function
code
Byte count Register 1
value Hi
Register 1
value Lo
Register 2
value Hi
Register 2
value Lo
CRC
Response [Hex]:
41
03
04
38
5F
41
D5
0A
E3
For decoding of float values (according IEEE754 format), please refer to AN0103, chapter 7 (page 6).
7.2 Modbus floating point format
E+E devices use the Modbus floating point format. The byte pairs 1, 2 and 3, 4 are inverted as follows:
MMMMMMMM
MMMMMMMM
SEEEEEEE
EMMMMMMM
Byte 3
Byte 4
Byte 1
Byte 2
Example:
Response [Hex] Value in decimal
41 D5 38 5F
26.652524
Protocol setting:
Address, baudrate, parity and stop bits can be set via:
1.
Product Configurator Software (available on www.epluse.com/EE660)
2.
Modbus protocol (please see Application Note Modbus (available on www.epluse.com/EE660)
