Sockets; Terminator, Status Byte, And Overload Byte - Ametek 7230 Instruction Manual

network can then access it, simply by typing the IP address in the address bar. As
discussed in section 5.4, this will open the Main Controls remote front panel.

6.5.04 Sockets

The instrument normally accepts commands sent to sockets 50000 or 50001 on its IP
address. Any response is sent back to the IP address from which the initiating
command was sent.
Clearly, if an instrument is present on a large network then it is possible that several
users may accidentally try to control the same instrument. To prevent this it is
possible to use the Bind control on the Rear Panel web control panel to restrict
access to the computer from which it is being viewed, which then becomes the only
one from which commands will be accepted.

6.5.05 Terminator, Status Byte, and Overload Byte

Commands sent to the instrument over the Ethernet interface should be terminated
with a null character (ASCII 0).
Responses from the instrument depend on whether port 50000 or 50001 is being
used, as follows:
Port 50000
Responses consist of a string that is terminated with three bytes, in the following
order:
1) A null character (ASCII 0)
2) A byte representing the value of the Status Byte (table 6-1)
3) A byte representing the value of the Overload Byte (table 6-1)
In the case of commands that generate a single response, the controlling program
should send the null-terminated command string to the instrument and then read
the response bytes sent back from it until the null is detected. Two further bytes
(the status and overload bytes) should then be read to complete the transfer.
Port 50001
Responses consist of a string that is terminated with one byte, as follows:
1) Carriage Return character (ASCII 13)
In the case of commands that generate a single response, the controlling program
should send the null-terminated command string to the instrument and then read
the response bytes sent back from it until the carriage return is detected.
Commands that do not return data still always return the one or three terminator
bytes, allowing the controlling program to know that the command has been
implemented.
Data stored in the instrument's curve buffer can be transferred in two ways. In the
ASCII mode, each value is terminated in a null character until the last value, which is
then terminated as above, whereas in the binary dump mode each data point occupies
two bytes, with the complete dump being terminated as above.
In either case it is necessary to know how much data will be transferred before
initiating the transfer, by sending the M (monitor) command and reading the
response. This is because in the ASCII dump mode the controlling program needs to
"count" each instance of a null character until all available points have been read,
Chapter 6, COMPUTER OPERATION
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