Proxima ASA 7911 - Manual (Page 94)

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that Windows Sockets programs require a compiler, such as
Visual C++, in order to be executed. On UNIX machines,
Berkeley Sockets is available on most of the common platforms.
5. The data sent to the Serial Adapter must be formatted appro-
priately. A four-byte header precedes the user data that is sent.
The contents of the four header bytes is as follows:
BYTE 1: Packet type
0= point-to-point (UDP or TCP), or 1= broadcast
BYTES 2 and 3: Packet length.
This is the length of the user data to be sent in this packet. The
allowable range of lengths is 1-1456 bytes. The length bytes are
arranged in network byte order.
BYTE 4: This byte is used to communicate RS-232 pin status to
other Serial Adapters. Use a value of 0F (Hex) to ensure that the
wired workstation and the Serial Adapter will communicate
without interruption.
The pin status byte includes the following information:
Bit 0 is set if DTR is asserted on the sending side; set this to a
value of 1 so that the Ethernet workstation will appear to have
DTR asserted.
Bit 1 is set if DSR is asserted on the sending side.
Bit 2 is set if RTS is asserted on the sending side; set this to a
value of 1 so that the Ethernet workstation will appear to have
RTS asserted.
Bit 3 is set if CTS is asserted on the sending side.