Apple 13-0010--001 Computer Drive User Manual


 
ELITE SERIES USER MANUAL SPECIFICATIONS
When this signal is high, the drive motor and
the busy light are turned off, the input control
and the output status lines are disabled, and
unused sections of the drive’s electronics
(Elite series) are powered down.
There is an intentional delay incorporated on
both the Elite and Disk II controller cards
which keeps a drive selected for a little over
one second after the software gives the command
to deselect the drive. This allows the software
to “reselect” the drive within that period with-
out having to wait for the motor to return to
operational speed.
This delay must be taken into account when the
software goes to select a drive on a different
controller card so that only one drive is power-
ed-up at any one time (an Apple II power supply
consideration). (The same consideration is
necessary when another device, such as Apple’s
Silentype printer, which draws power from the
Apple II power supply is to be selected.) No
pause is required when selecting an alternate
drive on the same controller since both the
Elite and Disk II controllers will immediately
deselect the previous drive when the new drive
is selected.
The select line must remain low throughout the
execution of a step or read/write command. After
the drive is selected, there must be a 500ms
delay before a write operation is initiated.
This 500ms delay allows the drive motor to come
up to speed. This delay is handled by the Apple
II operating systems.
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