Fujitsu MHA2021AT Computer Drive User Manual


 
5.4 Command Protocol
C141-E042-01EN 5-73
Note:
For transfer of a sector of data, the host needs to read Status register (X’1F7’) in order to
clear INTRQ (interrupt) signal. The Status register should be read within a period from the
DRQ setting by the device to 50 µs after the completion of the sector data transfer. Note that
the host does not need to read the Status register for the first and the last sector to be
transferred. If the timing to read the Status register does not meet above condition, normal
data transfer operation is not assured guaranteed.
When the host issues the command even if the drive requests the data transfer (DRQ bit is
set), or when the host executes resetting, the device correct operation is not guaranteed.
5.4.3 Commands without data transfer
Execution of the following commands does not involve data transfer between the
host and the device.
RECABLIBRATE
SEEK
READY VERIFY SECTOR(S)
EXECUTE DEVICE DIAGNOSTIC
INITIALIZE DEVICE PARAMETERS
SET FEATURES
SET MULTIPLE MODE
IDLE
IDLE IMMEDIATE
STANDBY
STANDBY IMMEDIATE
CHECK POWER MODE
SECURITY ERASE PREPARE
SECURITY FREEZE LOCK
Figure 5.6 shows the protocol for the command execution without data transfer.
Figure 5.6 Protocol for the command execution without data transfer