Flintec FT-10xx - Manual (Page 49)

FT-10 Smart Process Indicator, Technical Manual, Rev. 1.0, January 2014
8. M
ODBUS
RTU (
ONLY
FT-10 MB )
FT-10 MB indicator has a Modbus RTU interface over RS 485 / RS 232C serial port. This interface can be
programmable to High-Low or Low-
High for different type of PLC’s. You can find below the difference of
these data formats and some companies using these formats. Two types are available as;
8.1 Modbus RTU Data Structure
After programming RS 485 / RS 232C serial port for Modbus RTU, it can be used as a Modbus RTU slave on
Modbus RTU network. The Modbus slave address is defined in the RS-485 address (Page 25). Functions
code ‘0x03’ (Read Holding Registers) and ‘0x10’ (Preset Multiple Registers) are supported.
Modbus RTU High-Low: In two word registers, the data is stored to the registers in big-endian format. Least
significant word is stored to the highest register address; and most significant word is stored to the lowest
register address.
Modbus RTU Low-High: In two word registers, the data is stored to the registers in little-endian format.
Least significant word is stored to the lowest register address; and most significant word is stored to the
highest register address.
[00-] RS 232C Serial Port
This sub-block includes the parameters about the 1
st
serial interface of FT-10.
[000 3 ] Data Format
4 : Modbus RTU High-Low
5 : Modbus RTU Low-High
Set the RS 485 / RS 232C Data Format : Modbus
RTU High-Low or Modbus RTU Low-High
RS-485 Data Length & Parity : 8 none 1,
RS-485 Address : 01 to 31
Make the RS-485 / RS 232C parameter settings as defined on (Page 24).
Please find Modbus information in the web site of http://www.modbus.org
Modbus RTU Command Table;
Address R/W Word Command Definition
40001 R 2 Indicated weight ( Net if the indication is in Net )
40003 R 1 Status
D0 0 – System Ready 1 – System Busy
D1
0 – Error ( D13-D15
)
1 – Data ok
D2 0 – Weight Stable 1 – Weight unstable
D3 0 – Gross Mode 1 – Net mode
D4 –
D11
Not used
D12 0 – Out of zero range 1 – Weight is in zero range
D13
D14
D15
Error Code
De
c
Description
0 No Errors
1 ADC out of range
2 ADC over range
3 ADC under range
4 System error
5 In programming mode
6 Low/High voltage det.
40004 R 2 Tare weight
40006 R 2 Gross weight
40008 R 1 Status Motion, Net mode, Data ok, (image of register 40003)
40009
R/W 1 Control Dec Description