BASF 6106 - Index;Sector- and Ready Detector; Index;Sector Oetection

2.2.7 INDEX/SECTOR- AND READY DETECTOR
2.2.7.1 INDEX/SECTOR DETECTION
The index/sector detector comprises a photo-
transistor mounted on the deck assembly, a
light emitting diode (LED) on the pes and
a camparator (see Fig. 2-~4). As the index
hole or sec
tor (optional) hole passes bet-
ween LED and phototransistor. light fram the
LED is passed to the phototransistor. This
PHOTO
TRA:\SISTOR
P/J3
-
-
-
81---_
LED
+5V
results in a negative pulse of about 1.5 msec at
the inverting input of the comparator. The output
pulse of the comparator
is sent to the host system
by the output interface when 1/0 ENA is 3ctive.
Also the INDEX-pulse is used as input signal for
the ready detector logic.
.;.;.;. OUTPUT INTERFACE
'> __ ..... _T_J~2 .... -_8--'ltl----J n,,,,J TO '" :~~:'"
L,., .,,,~c,,,»y.,<j
1/0 ENA
FROH INPUT INTERFACE ..... !.!.!::...==--------"
FIGURE 2 - 24 INDEX DETECTOR
2 - 18