4.4 Various Processes
4.4 Various Processes
4.4.1 Reset response
There are four types of resets.
!
!
!
!
∀The ODD performs initialization such as initial diagnostics and default setting. If any media is mounted, it also spins up media.
Hardware reset
∀The ODD is reset when the RESET- signal is asserted. The ODD initializes the interface controller by setting default values.
∀UNIT ATTENTION is generated.
ATA software reset
∀The ODD is reset when the SRST bit of the Device Control register is set.
∀The device driver should not use the SRST bit to reset the ODD (except for restore from sleep mode).
∀After ATA software reset, the ODD initializes the task file as shown below.
Status = 00h
Error = (Depending on the SRST sequence) Sector Count = 01h
Sector number = 01h Cylinder Low = 14h Cylinder High = EBh Drive/Head = 00h
∀DRDY is set to 1 with the first command after ATA reset.
∀If ATA software reset is issued while the ODD is selected and a command is being executed (BSY = 1 or DRQ = 1), the command is interrupted. Otherwise, the ODD continues command processing.
∀The contents set with the MODE SELECT and Set Features commands remain unchanged.
ATAPI reset
∀The ODD is reset with a DEVICE RESET command. The ODD interrupts the current command.