pc8477b National Semiconductor Corporation, pc8477b Datasheet - Page 44

• Manufacturer Part Number: pc8477b
• Description: Advanced Floppy Disk Controller
• Manufacturer: National Semiconductor Corporation

6 0 Device Description
6 2 6 Reset Timing
Note 10 The software reset pulse width is 100 ns The hardware reset pulse width with an external 10 kX pull-up or pull-down resistor on the MFM pin is 100 ns
When using the internal pull-up resistor on the MFM pin the hardware reset pulse width is 170 ns (assumes no load on MFM)
6 2 7 Write Data Timing
Symbol
t
t
t
WDW
HDS
HDH
t
t
Symbol
RW
RC
Data Rate
1 Mb s
500 kb s
300 kb s
250 kb s
Write Data Pulse Width
HDSEL Setup to WGATE Active
HDSEL Hold from WGATE Inactive
Reset Width (Note 10)
Reset to Control Inactive
Parameter
Parameter
(Continued)
1000
2000
3333
4000
t
TABLE 6-2 Minimum t
DRP
FIGURE 6-6 Write Data Timing
FIGURE 6-5 Reset Timing
2 x t
2 x t
2 x t
2 x t
t
WDW
44
ICP
ICP
ICP
ICP
WDW
Min
100
Values
t
Table 6-2
WDW
Min
100
750
250
250
375
500
Value
Max
300
Units
ns
ns
ns
ns
Max
TL F 11332 – 21
TL F 11332 – 20
Units
ns
ns
Units
ns
ms
ms