Tektronix 7D20 Operator's Manual page 208

E.C . = EVENT CODE
S.B . = STATUS BYTE
ALLEVNT7
POLLED E.C .
YES
.PRESENT7~
NO
NO
PENDING E~(,'.
PRESENT
YES
SEND PENDING E.C .
CLEAR PENDING S.B .
SEND TOP E.C .
FROM E.C . LIFO BUFFER
E.C . LIFO
NO
E MPTY?
YES
'HAS E.C . YES
BEEN SENT
NO
SEND "NULL" E.C .
END ALLEVNT
HANDLER
Figure 4-17 . All-event query flow chart.
SEND POLLED
E.C .
GPI B-7D 20
3857-315
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