PS/2 Interface Mode
Table 5 - SRA PS/2 Mode
7
6
5
4
3
2
1
0
INT
nDRV2
STEP
nTRK0
HDSEL
nINDX
nWP
DIR
PENDING
RESET
0
1
0
N/A
0
N/A
N/A
0
CONDITION
Direction, Bit 0
Active high status indicating the direction of head movement. A logic “1” indicating inward direction, a logic “0”
outward.
nWRITE PROTECT, Bit 1
Active low status of the WRITE PROTECT disk interface input. A logic “0” indicating that the disk is write protected.
The nWRITE PROTECT bit also depends upon the state of the Force Write Protect bits in the Force FDD Status
Change configuration register (see section CR17).
nINDEX, Bit 2
Active low status of the INDEX disk interface input.
Head Select, Bit 3
Active high status of the HDSEL disk interface input. A logic “1” selects side 1 and a logic “0” selects side 0.
nTRACK 0, Bit 4
Active low status of the TRK0 disk interface input.
Step, Bit 5
Active high status of the STEP output disk interface output pin.
nDRV2, Bit 6
The nDRV2 bit is always “1”.
Interrupt Pending, Bit 7
Active high bit indicating the state of the Floppy Disk Interrupt output.
SMSC DS – FDC37N3869
Page 19
Rev. 10/25/2000
SMSC [ SMSC CORPORATION ]
