W83977AF Information Storage Devices, Inc, W83977AF Datasheet - Page 52

• Manufacturer Part Number: W83977AF
• Description: W83877TF Plus Kbc, Cir, RTC
• Manufacturer: Information Storage Devices, Inc

DRATE1 DRATE0 (Bit 2, 1):
These two bits select the data rate of the FDC. Refer to the DR register bits 1 and 0 for the settings
corresponding to the individual data rates.
0
1
In the PS/2 Model 30 mode, the bit definitions are as follows:
DSKCHG (Bit 7):
This bit indicates the status of DSKCHG input.
Bit 6-4: These bits are always a logic 1 during a read.
DMAEN (Bit 3):
This bit indicates the value of DO REGISTER bit 3.
NOPREC (Bit 2):
This bit indicates the value of CC REGISTER NOPREC bit.
DRATE1 DRATE0 (Bit 1, 0):
These two bits select the data rate of the FDC.
HIGH DENS (Bit 0):
500 KB/S or 1 MB/S data rate (high density FDD)
250 KB/S or 300 KB/S data rate
7
6
0
5
0
0
4
3
2
1
W83977F/ W83977AF
0
DSKCHG
DRATE0
DRATE1
NOPREC
DMAEN
Publication Release Date: March 1998
PRELIMINARY
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Revision 0.58