Specifications

4.14 Reset response
When the drive is reset, either by the host reset interface pin (RESET)
or by the host software reset bit (SRST) in the Device Control register,
the drive asserts BSY immediately. Once the reset has been removed
and the drive has been re-enabled, with BSY still asserted, the drive:
1. Initializes the hardware
2. Clears programmed drive parameters and reverts to the defaults
3. Loads the command block registers with their initial values
4. Negates DASP–
No interrupt is generated when initialization is complete. The initial values
for the command block registers are:
Register name Initial values
Error 01
H
Sector Count 01
H
Sector Number 01
H
Cylinder Low 00
H
Cylinder High 00
H
Drive Head 00
H
ATA Interface Reference Manual, Rev. C 23