Fujitsu MHV2040AS, MHV2080AS, MHV2060AS manual 1 I/O registers, DA2 DA1 DA0

5.2 Logical Interface

5.2.1 I/O registers

Communication between the host system and the device is done through input- output (I/O) registers of the device.

These I/O registers can be selected by the coded signals, CS0-, CS1-, and DA0 to DA2 from the host system. Table 5.2 shows the coding address and the function of I/O registers.

Table 5.2 I/O registers

CS0–	CS1–	DA2	DA1	DA0	I/O registers		Host I/O
					Read operation	Write operation	address
Command block registers
L	H	L	L	L	Data	Data	X’1F0’
L	H	L	L	H	Error Register	Features	X’1F1’
L	H	L	H	L	Sector Count	Sector Count	X’1F2’
L	H	L	H	H	Sector Number	Sector Number	X’1F3’
L	H	H	L	L	Cylinder Low	Cylinder Low	X’1F4’
L	H	H	L	H	Cylinder High	Cylinder High	X’1F5’
L	H	H	H	L	Device/Head	Device/Head	X’1F6’
L	H	H	H	H	Status	Command	X’1F7’
L	L	X	X	X	(Invalid)	(Invalid)	—
Control block registers
H	L	H	H	L	Alternate Status	Device Control	X’3F6’
H	L	H	H	H	—	—	X’3F7’

Notes:

1.The Data register for read or write operation can be accessed by 16 bit data bus (DATA0 to DATA15).

2.The registers for read or write operation other than the Data registers can be accessed by 8 bit data bus (DATA0 to DATA7).

3.When reading the Drive Address register, bit 7 is high-impedance state.

4.H indicates signal level High and L indicates signal level Low.

There are two methods for specifying the LBA mode. One method is to specify the LBA mode with 28-bit address information, and the other is to specify it with 48-bit address information (command of EXT system). If the LBA mode is specified with 28-bit address information, the

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