Patton electronics EtherBITS 2211, Руководство по началу работы

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Introduction 52
Models 2211 & 2232 Getting Started Guide 6 • Serial port configuration
The DSR option can be set to one of three types: none, allow TCP connection only by high or open/close TCP con-
nection. Allow TCP connection only by HIGH is valid only if host mode is TCP server or equivalent. If this
option is set, the incoming TCP connection request will be accepted only when the DSR signal is high state.
Open/close TCP connection is valid only if the host mode is a TCP client or equivalent. If the DSR behavior is
set to open/close TCP connection, the high state of the DSR pin will make the 2211 send a connection request to
the specified destination host, whereas the low state close a connection.
Inter-character timeout defines the interval that the 2211 fetches the overall serial data from its internal buffer. If
there is incoming data through the serial port, the 2211 stores data into the internal buffer. The 2211 transfers
data stored in the buffer via TCP/IP, only if the internal buffer is full or if the inter-character time interval
reaches to the time specified as inter-character timeout.
Optimal inter-character timeout would be different according to your application but at least it must be larger
than one character interval within specified baud rate. For example, assume that the serial port is set to 1200
bps, 8 Data bits, 1 stop bit, and no parity. In this case, the total number of bits to send a character is 10 bits
and the time required to transfer one character is
10 (bits) / 1200 (bits/s) * 1000 (ms/s) = 8.3 ms.
Therefore, you have to set inter-character timeout to be larger than 8.3 ms. The inter-character timeout is spec-
ified in milliseconds and must be larger than 10 ms.
If users want to send the series of characters into a packet, serial device attached to the 2211 should send char-
acters without time delay larger than inter-character timeout between characters and the total length of data
must be smaller than or equal to the 2211 internal buffer size. The serial communication buffer size of 2211 is
1400 bytes.
The following example shows a serial port configuration of 9600 bps, 7 data bits, even parity, 2 stop bits, hard-
ware flow control, DTR shows TCP connection, No DSR behavior and inter-character time out of 10 ms:
> set serial 9600 7 e 2 h s n 10
OK
>