4.0
Operation procedures and precautions
4.1
Power-on procedure
The
power supply can be turned on in any order. The write gate signal should be
held at a high level so that the power-on action does not cause illegal writing. An
interval of 700ms is necessary between power-on time and operation-start time.
After powering on, the initial position of the read/write head is at Track 00. Because
of this, a recalibrate operation is not required.
4.2
Drive selection
The drive is selected when the DRIVE SELECT signal goes to a low level. Under
this operation, the input and output lines are enabled.
4.3
Drive motor turn-on
Throughout data reading and writing, the drive motor must rotate at a constant
speed. The drive motor is activated when the MOTOR ON signal is set at low level,
and requires 500ms to reach constant speed. When the MOTOR ON signal
changes to a high level, the drive motor stops after about 4 seconds. The motor
must be turned off if the drive has not received a new command by host system by
deactivating the MOTOR ON signal. This ensures maximum motor and media life.
When the media detector detects a change point due to insertion, the drive motor
rotates for about 10 seconds. An option is available to turn it on/off with the DRIVE
SELECT signal.
4.4
Precautions
1. Upon installation, pay close attention to reducing the ambient electrical noise,
such as the noise from the switching power supply or CRT.
2. The drive automatically rotates the spindle motor when a diskette is inserted, for
better clamping accuracy. This also prevents the diskette from being damaged
upon clamping. For full use of this feature, turn the power on before inserting a
diskette.
5.0
Timing diagram
The step, read, write and general control timings are given on the following pages.
Note:
Min. = The minimum amount of time the controller must wait for the execution of
the next operation.
Max. = The maximum amount of time required by the drive to complete an
operation. The maximum amount of time delay allowed by the controller for
next operation: i.e. the controller must execute (start to stop) an operation
within the maximum limit amount of time.
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Leaflet No. 9419 26/4/97 6:10 pm Page 23
