Omron E5AN Communications Manual page 88

SECTION 5 Modbus Communications Procedure
● Number of Elements
● Set Values
5-8
Setup area 0 and setup area 1 do not correspond directly to Modbus
addresses, but the following areas have a rough correspondence with
one exception.
Setup area
Area number
Setup area 0 00 to 0B, 20 to 2B
Setup area 1 0C to 13, 2C to 33
* Partial Exception to Modbus Address Correspondence
The Hysteresis (Heating), Hysteresis (Cooling), Control Period
(Heating), and Control Period (Cooling) parameters are assigned to
consecutive addresses, but the control period parameters are setup
area 1 parameters. For this reason, an operation error will occur when
writing the control period (heating or cooling) from the setup area 0
side, e.g., from the operation level.
The number of elements is expressed in 2-byte hexadecimal. The
setting range for the number of elements varies according to the
command.
For example, when the number of elements is "0010," this specifies
eight items of data (H'10) from the address.
• Four-byte Mode
One element uses 2 bytes of data, so specify two-element units.
Reading and writing in 4-byte units is executed by specifying an even
address and specifying the number of elements in multiples of 2.
• Two-byte Mode
One element uses 2 bytes of data, so specify one-element units.
Reading and writing in 2-byte data units is executed by specifying 1-
element units.
The values read from the variable area or written to the variable area
are expressed in hexadecimal, ignoring the decimal point position.
(Negative values are expressed in 2's complement format.)
Example: D'105.0 → H'0000041A
The variables are 4-digit or 8-digit hexadecimal values. Negative values
are expressed in 2's complement format. The values are hexadecimal
values with no decimal point indication.
For example, if the E5CN/AN/EN/GN's process value is read in 4-byte
mode when the process value is 105.0, the read value will be
H'0000041A (105.0 → 1050 → H'0000041A).
Modbus addresses
Address range
0000 to 0BFE,
2000 to 2B7F
0C00 to 1366,
2C00 to 3333