PSI BOX PLUS+ Reference
Control Functions
STATUS.
Send The Status String To RS232 Host.
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Purpose.
To cause the PSI BOX to send the IEEE control
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string back to the host RS232 computer.
The PSI BOX stores a table of data that it uses to inform
itself of which devices to access and in what manner it should
control the bus. This table of data is called the IEEE control
status string. The IEEE control status string also holds
information on parallel and serial poll responses, time out data,
byte counts of data transferred during the previous i/o and many
other interesting parameters. The first field of the IEEE control
status string holds the current IEEE device number, the second
field is that device’s secondary address.
The current PSI BOX status string will be sent from the
PSI BOX to the RS232 host computer whenever the PSI BOX
receives the STATUS command.
Alternatively, for increased ease of use, a BUS command
without any parameters or keywords will be treated as a
STATUS command. Any spaces after BUS but before the <CR>
are ignored.
The IEEE control string can be obtained in a more human
readable form by the SHOW command.
A request for the STATUS causes the PSI BOX to return the
IEEE control status string to the RS232 host computer. This is a
string of Ascii characters preceded by the word STATUS and
terminated by a CR character, decimal 13. The string is made up
of a series of numbers separated by commas and looks like:-
STATUS 04, ,0,1,1,0,00,00000,00000,000,000,000,0,0,1 etc
Currently the IEEE control status string is approximately
90 bytes long, as new features are added to the PSI BOX
software the length of the control status string increases. It is
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