User guide

eWON 500-2001-4001-4002 User Guide - IO Servers Configuration
eWON 500®2001®4001®4002® Version 4_3_0 - User Guide - 10/5/05 - ©ACT'L sa - Page 82
After the numerical value, the characters F, L, I, D or W can be used to specify how to read the value.
The following table describes the different character meaning.
When reading a 32 bits value, two consecutive registers or coils are read and combined, i.e. 40001F,11
to access in float representation the reg 1 on the slave 11.
Reading high 32 bits values involve a lost of precision in the mantissa because internally all values are considered as float by the eWON.
STATUS TAG:
The STATUS Tag is a special Tag that returns information about the current state of the communication for a given device. As for other Tags,
the status Tag ItemName is composed of:
Status,Address
If address is omitted, the Topic address will be used. i.e.: status,11 points to the status of the slave 11
You can define a status Tag for each address used.
If you use the status MODBUS address, the Tag must be configured as analog:
6.3.3.2 Slave Address
This is the address of the slave device you want to access.
It is a number from 0 to 255.
Example:
6.3.3.3 IP Address
This is the IP address of the device on an Ethernet network. It is composed of 4 numbers separated by a dot.
Example:
Character Description
W Reads 1 register considered as 16 bits unsigned integer (DEFAULT IF NOT SPECIFIED)
I Reads 1 register considered as 16 bits signed integer
D Reads 2 regs R1, R2 as a DWORD R1 is Less significant, R2 is most significant (32 bits, unsigned)
E Reads 2 regs R1, R2 as a DWORD R2 is Less significant, R1 is most significant (32 bits, unsigned)
L Reads 2 regs R1, R2 as a LONG R1 is Less significant, R2 is most significant (32 bits, signed)
M Reads 2 regs R1, R2 as a LONG R2 is Less significant, R1 is most significant (32 bits, signed)
F Reads 2 regs R1, R2 as a FLOAT R1 is Less significant, R2 is most significant (32 bits, signed)
H Reads 2 regs R1, R2 as a FLOAT R2 is Less significant, R1 is most significant (32 bits, signed)
Table 54: the characters used to specify how to read the value
Tag value Meaning
0
Communication not initialized. Status UNKNOWN.
If no Tag is polled on that device address, the communication status is unknown.
1 Communication OK.
2 Communication NOT OK.
Table 55: MODBUS status values
30001,11 Polls a RTU device at address 11.
30001,11,10.0.0.50 Polls a device configured with IP address 10.0.0.50 and with Modbus slave address 11.