W83977F-A Datasheet, PDF (36/182 Pages) Winbond – WINBOND I/O

W83977F-A/ W83977G-A/ W83977AF-A/ W83977AG-A
5.2.1 Status Register A (SA Register) (Read base address + 0)
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:
765 43 ²¹ 0
INIT PENDING (Bit 7):
This bit indicates the value of the floppy disk interrupt output.
DIR
WP
INDEX
HEAD
TRAK0
STEP
DRV2
INIT PENDING
DRV2 (Bit 6):
0 A second drive has been installed
1 A second drive has not been installed
STEP (Bit 5):
This bit indicates the complement of STEP output.
TRAK0 (Bit 4):
This bit indicates the value of TRAK0 input.
HEAD (Bit 3):
This bit indicates the complement of HEAD output.
0 side 0
1 side 1
INDEX (Bit 2):
This bit indicates the value of INDEX output.
WP _{(Bit 1):}
0disk is write-protected
1disk is not write-protected
DIR (Bit 0)
This bit indicates the direction of head movement.
0 outward direction
1 inward direction
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