Table 19 - Data Rates
DATA RATE
DRIVE RATE
SELECT
DATA RATE
SELECT
DENSEL
(Note 1)
(DSR)
(CR0B)
DRATE
DRT1
DRT0
SEL1
SEL0
MFM
1Meg
500
300
250
1Meg
500
500
250
1Meg
500
FM
---
IDENT=1
IDENT=0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
0
0
0
0
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
0
0
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
1
0
1
1
0
0
1
1
0
0
1
1
0
0
0
0
1
1
0
0
1
1
0
0
1
1
1
0
0
1
1
0
0
1
1
0
0
1
250
150
125
---
250
250
125
---
250
---
2Meg
250
125
Note 1: This is for DENSEL in normal mode (see section CR05 on page 102). The DENSEL pin is set high after a
hardware reset and is unaffected by the DOR and the DSR resets.
Table 20 - Drive Rate Table (Recommended)
DRIVE RATE
FORMAT
(see section CR0B on page 104 to program Drive Rate)
360K, 1.2M, 720K, 1.44M and 2.88M Vertical Format
3-Mode Drive
DRT1
DRT0
0
0
1
0
1
0
2 Meg Tape
Table 21 - Default Precompensation Delays
PRECOMPENSATION
DELAYS
125 ns
41.67 ns
125 ns
125 ns
125 ns
DATA RATE
2 Mbps
1 Mbps
500 Kbps
300 Kbps
250 Kbps
SMSC DS – FDC37N3869
Page 27
Rev. 10/25/2000
SMSC [ SMSC CORPORATION ]
