FUJITSU MHD2032AT - Manual (Page 58)

4.6 Read/write Circuit
C141-E050-02EN 4-9
Table 4.1 Self-calibration execution timechart
Time elapsed Time elapsed
(accumulated)
1 At power-on Initial calibration
2 About 5 minutes About 5 minutes
3 About 5 minutes About 10 minutes
4 About 10 minutes About 20 minutes
5 About 10 minutes About 30 minutes
6 About 15 minutes About 45 minutes
7 About 15 minutes About 60 minutes
8
.
.
.
.
Every about 30
minutes
4.5.3 Command processing during self-calibration
If the disk drive receives a command execution request from the host while
executing self-calibration according to the timechart, the disk drive terminates
self-calibration and starts executing the command precedingly. In other words, if
a disk read or write service is necessary, the disk drive positions the head to the
track requested by the host, reads or writes data, and restarts calibration.
This enables the host to execute the command without waiting for a long time,
even when the disk drive is performing self-calibration. The command execution
wait time is about maximum 100 ms.
4.6 Read/write Circuit
The read/write circuit consists of the read/write preamplifier (PreAMP), the write
circuit, the read circuit, and the time base generator in the read channel (RDC).
Figure 4.4 is a block diagram of the read/write circuit.
4.6.1 Read/write preamplifier (PreAMP)
One PreAMP is mounted on the FPC. The PreAMP consists of an read
preamplifier and a write current switch and senses a write error. Each channel is
connected to each data head. The head IC switches the heads by the chip select
signals (*CS) and the head select signals. The IC generates a write error sense