CSE-H25 User
’
s Manual Ver. 1.2
Sollae Systems Co., Ltd.
- 29 -
http://www.sollae.co.kr
5.2
T2S
–
TCP Server
In T2S mode, the CSE-H25 functions as a server.
When a host connects to predefined local port, the CSE-H25 accepts a TCP
connection. When the ezTCP accepts TCP connection, then the TCP connection is
established. After connection is established, TCP/IP processing is performed on the data
coming to the serial port, which is then transmitted to the remote host. And the TCP/IP
data coming from the remote host is TCP/IP-processed and transmitted to the serial port
to establish data communication.
Remote Host
Serial Device
ezTCP
Listen on
local port
Request TCP connection
Accept TCP co
nnection
ack
DATA
“
ABC
”
DATA
“
ABC
”
(TCP/IP)
DATA
“
DEF
”
(TCP/IP)
DATA
“
DEF
”
connected
<T2S Mode>
5.2.1 TCP Connection
If a host connects to the pre-defined [Local Port] of CSE-H25, the host can
communicate bi-directionally.
5.2.2 Serial Data before the TCP Connection
The received serial data before the TCP connection is established will be handled based
on the [Event Byte] settings. If the [Event Byte] is 0, the data that comes to serial port of
CSE-H25 will not be recognized. If it is not 0, the serial data before TCP connection will be
temporarily saved to be sent to the host after the connection.
5.2.3 Data Transmission
When the TCP connection is established, the data communication in between the host
and the serial device will be established. Then, CSE-H25 will send data according to the
[Data Frame]. In other words, when the data comes through CSE-H25‟s serial port, it will
be temporarily saved in the buffer. Then, when there is no incoming data during the
