Fujitsu MCF3064AP 7 Bit definitions of Drive Address register, ATAPI Byte Count register

4.3.1.5Drive Address register

This register's bits are defined as shown below.

		Table 4.7 Bit definitions of Drive Address register
7	6	5	4	3	2	1	0
HiZ	nWTG	nHS3	nHS2	nHS1	nHS0	nDS1	nDS0	Read

!HiZ is always in the high-impedance state.

!nWTG indicates the status of the ODD internal data write control signal (Write Gate).

!nHS3 indicates a binary complement of bits 3 to 0 of the drive select register.

!nDS1 is the device select bit for device 1. It is 0 when device 1 is selected.

!nDS0 is the device select bit for device 0. It is 0 when device 0 is selected.

4.3.1.6ATAPI Byte Count register

This register's bits are defined as shown below.

Table 4.8 Bit definitions of ATAPI Byte Count register

7 6 5 4 3 2 1 0

Byte Count (Bits 0-7)

Byte Count (Bits 8-15)

R/W

R/W

!This register is used for PIO transfer only. The ODD sets the byte count to be transferred by the host in this register and sets DRQ to 1. The ODD does not update this register until transfer starts.

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