7.1 Eight, 16, Or 32 Sectors
The SA801 , as shipped from the factory, is set up to provide 32 Sector pulses per revolution of the Diskette
onto the interface. This
option
is provided for the user
who
wishes to have eight
or
16 Sectors per revolution.
The logic divides the Sector pulses by
two
or
four. Reference Figure 29 for the timing relationships.
To install this option on a standard drive (SA801), the following
traces
should be added
or
deleted:
1.
Cut
trace
'32'.
2.
Connect
trace
'16'
for 16 Sectors
or
connect
trace
'8'
for eight Sectors.
Figure 30 illustrates the circuitry.
INDEX
32 SECTORS
16 SECTORS
8 SECTORS
I_
..
1
10
.4 ± .4 MS
l..-S----,~_l
l'
,
~
20.8 ± .6
Ms----II~-.l1
___
.......
-----l
1 _
* INDICATES BEGINNING OF SECTOR 1 IN RELATIONSHIP TO INDEX
Figure 29. Sector Timing Relationships
+SECTOR
8
-SECTOR
......
STANDARD TRACE
II{AI
DELETED (CUT) TRACE
...-.
ADDED TRACE
+ DRIVE SELECT
32
-INDEX
Figure 30. Sector Divide Circuit
35
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