EtherPath-X4 User’s Guide
When set to 1
, the timer is a serial port idle time value. If there is data in the buffer and the serial port has
been idle for TIMER msec, then an IP packet is transmitted.
2. Block Size
The
maximum
ethernet packet buffer size. The minimum value is 1 byte, the maximum 4096 bytes (4 K).
Typical values are either in a low range of 10-20 characters for polling applications or very large in the
range of 500 to 1500 for file transfer applications. Normally, the timer triggers a packet transmission
before the block fills. If the buffer contains BLOCKSIZE characters, an IP packet is transmitted regardless
of the timer mode and settings. This is normally left at 1500 so other factors control the packet
transmissions.
3. Flow Control OFF Buffer Level
If the amount of data stored in the buffer reaches this point, and the EtherPath is unable to transmit the data,
then no further input will be accepted.
Under normal operation, this will not happen. This is normally left at the default value.
4. Flow Control ON Buffer Level
Once the High_Water mark has been reached, the “no-input accepted” mode will continue until the
EtherPath has transmitted enough data to reduce the buffer contents to this point. This is normally left at
the default value.
5. Line_Terminator_Character
This setting is used to change the Line Terminator Character. The Line Terminator Character causes any
data in the buffer to be transmitted immediately the character is received, provided: This is the binary value
of the trigger charaacter.
•
The EtherPath is being used in “Client” mode.
•
The following setting (Transmit_on_LT_Char) is ON.
6. Transmit_on_LT_Char
When this setting is ON, any data in the buffer will be sent immediately upon receipt of a
Line_Terminator_Character (see previous setting). When the setting is OFF, the
Line_Terminator_Character has no effect.
In “Server” mode, this setting has no effect.
7. Server End-of-Line Filter
This setting can turn the filter function ON or OFF.
•
When ON in "Server" mode, all CR/LF (Carriage Return, Line Feed) and CR/NULL character pairs
received from the remote client are converted to CR only. CR/LF pairs are normally used in the MS-
DOS environment to mark the end of a line, but may cause problems in other environments which
expect a CR only.
•
When OFF all CR/LF and CR/NULL character pairs are handled as normal data.
•
This setting is ignored in "Client" mode.
8. Client Local Character Echo
If ECHO is ON, the client EtherPath will locally echo all incoming characters in client mode.
If ECHO is OFF, the client EtherPath will not echo characters or transmit any status messages to the serial
port. This mode should be used if any messages from the EtherPath would create interference.
OFF is the most commonly used value.
9. Keep-Alive Frequency
24
