Theory of Device Operation
4.4 Power-on Sequence
Figure 4.3 describes the operation sequence of the disk drive at power-on. The outline is described below.
a)After the power is turned on, the disk drive executes the MPU bus test, internal register read/write test, and work RAM read/write test. When the self-diagnosis terminates successfully, the disk drive starts the spindle motor.
b)The disk drive executes self-diagnosis (data buffer read/write test) after enabling response to the ATA bus.
c)After confirming that the spindle motor has reached rated speed, the head assembly is loaded on the disk.
d)The disk drive positions the heads onto the SA area and reads out the system information.
e)The disk drive sets up a requirement for execution of self -calibration. This collects data for VCM torque and mechanical external forces applied to the actuator, and updates the calibrating value.
f)The drive becomes ready. The host can issue commands.
Power-on
a)
b)
c)
Start
-MPU bus test
-Internal register write/read test
-Work RAM write/read test
The spindle motor starts.
-Data buffer write/read test
Confirming spindle motor speed
Load the head assembly
d)
e)
f)
Initial
Execute
Drive ready state (command waiting state)
End
