Fujitsu MPG3102AH, Product Manual

Page: 141 / 195

C141-E112-01EN 5 - 74
a) The host writes any required parameters to the Features, Sector Count, Sector Number,
Cylinder, and Device/Head registers.
b) The host writes a command code in the Command register. The drive sets the BSY bit of the
Status register.
c) When the device is ready to receive the data of the first sector, the device sets DRQ bit and
clears BSY bit.
d) The host writes one sector of data through the Data register.
e) The device clears the DRQ bit and sets the BSY bit.
f) When the drive completes transferring the data of the sector, the device clears BSY bit and
asserts INTRQ signal. If transfer of another sector is requested, the drive sets the DRQ bit.
g) After detecting the INTRQ signal assertion, the host reads the Status register.
h) The device resets INTRQ (the interrupt signal).
i) If transfer of another sector is requested, steps d) and after are repeated.
Figure 5.4 shows an example of WRITE SECTOR(S) command protocol, and Figure 5.3 shows
an example protocol for command abort.
Status read Status read
255 2 1 0 Word
IOCS16
IOR-
Data
Data Reg. Selection
DRQ Max. 1
µ
s
Expanded
Command
e c
d d
h
g g f
b
a
Command
BSY
INTRQ
DRDY
~
Parameter write
DRQ
Data transfer
• • • •
• • •
• • • •
• • • •
• • • •
• • • •
Figure 5.4 WRITE SECTOR(S) command protocol