E2648_UM_EN. Annex 1. E2648 series Modbus RTU Communication Reference
RS485 communication interface
Databits: 8
Parity: none
Stop bits: 1 or 2
Protocol: Modbus RTU
Supported Modbus functions:
03 - read multiple registers
06 - write single register
Communication parameters
Parameter
Permitted values
Default
Supported
baudrates
1200, 2400, 4800, 9600, 19200,
38400, 57600
9600
Data bits
8
8
Parity
none
none
Stop bits
1, 2
1
Protocol
Modbus RTU
Modbus functions
03 - read multiple registers
06 - write single register
Error codes
01 - illegal function
02 - illegal data address
03 - illegal data value
04 - slave device failure (details of last error 04
can be read from register 0x0008)
E2648 series Modbus holding registers
Register addresses are shown 0-based, Addr in hexadecimal, Reg in decimal format.
Modbus holding register numbers MHR are shown in decimal 1-based format, and may be addressed either from 00001 or 40001 base.
Addr
Holding register
RW
Description
Supported values (dec)
Default
0x0001
1
R
Hardware version
-
0x0002
2
R
Software version
-
0x0003
3
R
Product serial number
1...65535
-
0x0004
4
RW
Slave ID (net address) *
1...247 **
1
0x0005
5
RW
Baudrate *
1200, 2400, 4800, 9600, 19200, 38400, 57600
9600
0x0006
6
RW
Response delay, ms
1...255
10
0x0007
7
RW
Stop bits *
1: no parity bit, 1 stop bit (default after factory reset)
2: no parity bit, 2 stop bits
3: odd parity, 1 stop bit
4: even parity, 1 stop bit
NOTE
: 3 and 4 are available starting from the Sofrware version 0x218 (dec. 536)
1
0x0008
8
R
Last error code
1...255
-
0x0011
17
RW
Restarts counter
write ‘42330’ to restart device (no response will follow)
-
0x0097
151
R
Sensor type code
0...65535
0
* - The new value is applied after restart.
** - Broadcast slave ID 0 can be used to assign a new ID to device with unknown ID. When addressing by ID 0 the device shall be the
only Modbus instrument in the network. The device will not respond to Master command when addressed by ID 0.
*** - This value is dynamic and not kept in EEPROM after restart
