November 1985
National Instruments
SERIAL PORT ERROR CONDITIONS
Numeric
Symbolic
Value (n) Value (s)
Description
NSER
EPAR
EORN
EOFL
EFRM
No serial port error
condition to report
Serial port parity error
Serial port overrun error
Serial port receive buffer
overflow
Serial port framing error
A detailed description of the conditions under which
each bit in status is set or cleared may be found in
Appendix
In general, the GPIB-MAC updates the first three status
variables at the end of each programming message. It
updates the fourth, count, after a cmd, rd, or
wrt
function The errors reported correspond to the previous
programming message. For example, if you call wrt
and then stat s, any errors returned to you correspond
to errors in the
wrt
programming message, not
stat.
However, if status is returned in continuous mode, the
status information corresponds to the current
programming message. For example, suppose you call
stat c to set up continuous status reporting. After
reading the status information returned for the
stat call,
you call wrt. The
GPIB-MAC then returns the status
information that corresponds to the wrt message.
Refer to the following examples for ways in which to
make use of the status information.
When you wish to begin continuous status reporting,
send the stat c s, stat c n, or stat c
n
programming
message. Status information will be immediately
returned indicating the current status conditions. When
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SECTION FOUR FUNCTIONS