Fujitsu MHU2100AT, Product Manual

Page: 62 / 278

Theory of Device Operation
4-6 C141-E202-01EN
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.
Figure 4.3 Power-on operation sequence
Start
Self-diagnosis 1
- MPU bus test
- Internal register
write/read test
- Work RAM write/read
test
Power-on
a)
The spindle motor starts.
Self-diagnosis 2
- Data buffer write/read
test
b)
Confirming spindle motor
speed
c)
Load the head assembly
Drive ready state
(command waiting state)
f)
Execute self-calibration
e)
Initial on-track and read
out of system information
d)
End