A0-15 (ISA)

AEN

nIOWR

t3

nIORD

Z

D0-7

VALID ADDRESS

t5

VALID DATA OUT

VALID ADDRESS

t3

t7

Z

VALID DATA IN

t8

 

Parameter

min

typ

max

units

 

 

 

 

 

 

t3

Address, nSBHE, AEN Setup to Control Active

25

 

 

ns

t5

nIORD Low to Valid Data

 

 

40

ns

t7

Data Setup to nIOWR Rising

30

 

 

ns

t8

Data Hold after nIOWR Rising

9

 

 

ns

 

 

 

 

 

 

FIGURE 32 - 8-BIT MODE REGISTER CYCLES

A0-19

ADDRESS VALID

t3

t4

nMEMRD

Z

D0-15

 

Parameter

min

typ

max

units

 

 

 

 

 

 

t3

Address Setup to Control Active

25

 

 

ns

t4

Address Hold after Control Inactive

20

 

 

ns

t16

nMEMRD Low to nROM Low

0

 

25

ns

t17

nMEMRD High to nROM High

0

 

30

ns

 

 

 

 

 

 

BALE tied high

FIGURE 33 - EXTERNAL ROM READ ACCESS

124

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SMC Networks SMC91C95 manual BIT Mode Register Cycles, 124