Xinje XDH Series User Manual

282
6-3-3 Suitable occasion
When does free communication need to be used?
As an example, the situation described in the above section is that XINJE PLC communicates
with the temperature control instrument, and the instrument uses its own communication
protocol, which stipulates that the reading temperature should be sent four characters: "R",
"T", "CR". Each character has the following meanings:
Character
Meaning
：
Data start
R
Read
T
temperature
CR
Enter, data end
PLC needs to send the ASCII code of the above characters to the instrument in order to read
the current temperature value measured by the instrument. The ASCII code values
(hexadecimal) of each character can be obtained by querying the ASCII code table.
Character
ASCII code value
：
3A
R
52
T
54
CR
0D
Obviously, according to the situation described above, using MODBUS instructions can not
communicate, at this time you need to use free communication. Detailed usage will be used as
an example to program the sample program in later chapters.
6-3-4 Free communication instruction
Send data [SEND]
1)Summary
Write the local data to specified remote station address.
Send data [SEND]
16 bits
instruction
SEND
32 bits
instruction
-
Execution
condition
Normally ON/OFF, rising
edge triggering
Suitable
model
XD, XL
Hardware
V3.2.3 and higher version
Software
V3.2.2 and higher version
2)Operand
Operands
Function
Type
S1
Local data starting address
16 bits, BIN
S2
Send byte number
16 bits, BIN
n
Communication port no.
16 bits, BIN
tudonghoatoancau.com

Xinje XDH Series Specifications

General

Brand	Xinje
Model	XDH Series
Category	Network Hardware
Language	English