Philips System 21 Quick Operating Manual page 23

Requested data
Command data
Description
Response data
0
System 21 status
" STA ? "
Request system 21 STAtus.
Response: "STA"
+
<9 digits>
digits:
" 1" Master detected a power-on reset.
" 2" The addressed unit was not
present.
" 3" A unit is busy.
"4" A unit is not ready with the
received data.
"5"
A unit has data available and
should be read.
" 6" One or more units are busy with a
block or scan .
"7''
A unit has a warning.
" 8"
The master detected the ready-
line high; ready is true (available
on PM 2101 master; not available
on all masters) .
" 9"
The master captured a trigger pulse
on the trigger-line (available on
PM2101 master; not available on all
masters).
Digits " 1", " 2", " 8" and " 9" are
cleared when read .
A digit which is " 0", indicates that
the related message is not true.
Example:
" STA 103056700"
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