w83977ctf Winbond Electronics Corp America, w83977ctf Datasheet - Page 44

• Manufacturer Part Number: w83977ctf
• Description: Winbond I/o
• Manufacturer: Winbond Electronics Corp America

INDEX (Bit 2):
This bit indicates the complement of INDEX# output.
WP (Bit 1):
0
1
DIR#(Bit 0)
This bit indicates the direction of head movement.
0
1
2.2.2 Status Register B (SB Register) (Read base address + 1)
This register is used to monitor several disk interface pins in PS/2 and Model 30 modes. In PS/2
mode, the bit definitions for this register are as follows:
Drive SEL0 (Bit 5):
This bit indicates the status of DO REGISTER bit 0 (drive select bit 0).
WDATA Toggle (Bit 4):
This bit changes state at every rising edge of the WD# output pin.
RDATA Toggle (Bit 3):
This bit changes state at every rising edge of the RDATA# output pin.
WE (Bit 2):
This bit indicates the complement of the WE# output pin.
MOT EN B (Bit 1)
This bit indicates the complement of the MOB# output pin.
MOT EN A (Bit 0)
This bit indicates the complement of the MOA# output pin.
In PS/2 Model 30 mode, the bit definitions for this register are as follows:
disk is not write-protected
disk is write-protected
inward direction
outward direction
7
1
6
1
5
4
3
-35 -
2
1
0
MOT EN A
MOT EN B
WDATA Toggle
WE
RDATA Toggle
Drive SEL0
Publication Release Date: March 1999
W83977EF/ CTF
PRELIMINARY
Revision A1