NS486SXL NSC [National Semiconductor], NS486SXL Datasheet - Page 21

• Manufacturer Part Number: NS486SXL
• Description: Optimized 32-Bit 486-Class Controller with On-Chip Peripherals for Embedded Systems
• Manufacturer: NSC [National Semiconductor]

ISA-like Bus Cycles Timing Specification
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
Symbol
Symbol
Symbol
RCDH
WCDH
WCVD
WCS
AHCD
ASCD
CDPW
CHCD
CSCD
DOFF
RCAT
RCDH
WCDH
WCVD
WCS
RACD
RDYH
RDYL
Note 12: The value of (Wait) in the above formulae, is the number of programmed wait states associated with that access cycle (default value is 7, but may be pro-
grammed to 0–7).
Note 13: The value of (Wait) in the above formulae, is the number of programmed wait states associated with that access cycle (default value is 7, but may be pro-
grammed to 0–7).
Note 14: For this case Valid Write Data Sets-up to the leading edge of the Command Strobe.
Ready Feedback Timing Specifications
Note 15: The value of (Wait) in the above formulae, is the number of programmed wait states associated with that access cycle (default value is 7, but may be pro-
grammed to 0–7). The value of (E_RDY) in the above formulae, is the number of programmed extended ready states associated with every access cycle (default
number is 2, but may be programmed to 0–2).
Read CMD Data Hold Time
Write CMD Data Hold Time
Write CMD to Valid Data
Write Command Setup Time
Address Hold Time from CMD
Address Setup Time to CMD
Command Pulse Width
Chip Select Hold Time from CMD
Chip Select Setup Time to CMD
Read Data TRI-STATE
Read CMD Data Access Time
Read CMD Data Hold Time
Write CMD Data Hold Time
Write Valid Data to CMD (Note 14)
Write Command Setup Time
RDY Active to CMD Rising
RDY Hold Time from CMD
CMD to RDY Inactive Feedback
TABLE 20. One Programmed Command Delay ISA-like Bus Specifications
TABLE 19. No Command Delay ISA-like Bus Specifications (Continued)
Parameter
Parameter
TABLE 21. Ready Signal Timing Specifications
Parameter
FIGURE 10. Ready Feedback Timing Diagram
21
(Continued)
1.0T + (Wait)T +
1.0T + (Wait)T +
1.0T + (Wait)T +
(E_RDY)T +
Formula
Formula
Formula
1.0T +
0.5T +
1.0T +
2.0T +
1.0T +
2.0T +
1.0T +
1.0T +
1.0T +
0.5T +
Min
Min
Min
−25
−20
−20
−20
−10
−25
−40
−25
−20
−5
0
0
0
0
DS100121-15
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Max
Max
Max
−25
−30
−30
5