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c
HAPTER
4:
Computer Interface Operation
F71/F41 Teslameter
of the teslameter, the protocol is used to create a communication channel between
one program on one computer and the command line interface of the teslameter. TCP
uses error correction and collision avoidance schemes that make it a very reliable
form of network communication, but has drawbacks of having nondeterministic tim-
ing, and can encounter relatively large delays depending on network conditions.
These delays can be on the order of seconds. Sockets use port numbers to identify
sending and receiving endpoints on network devices. This allows for multiple sepa-
rate communication links to exist on each device.
The port number used for TCP socket connections on the teslameter is 7777 by default.
The port number can be configured from the Connectivity screen in System settings (top
left corner of the screen).
4.4.3 SCPI over TCP
There may be scenarios where the user desires to have the teslameter connected to
the internet but does not want anyone to be able to connect to the teslameter and
start controlling it. The SCPI over TCP setting allows for this. If the setting is disabled,
network connections are still allowed, allowing firmware or autodate time to still
function. For example, remote control of the teslameter will not be allowed even if
another user knows the IP address and socket of the teslameter.
In order to issue SCPI commands over TCP and remotely control the instrument, this
setting needs to be enabled. This can be done by touching the switch, as shown below.
FIGURE 4-12
SCPI over TCP
