25˚C. (Continued)

Symbol

Parameter

Conditions

Typical

Limits

Units

(Note 8)

(Note 9)

(Limits)

ISA READ TIMING

t

Data Valid to IORD Inactive

120

ns (min)

t

IORD Inactive to Data Invalid

5

ns (min)

t

IORD Active to Rising Edge of SYSCLK

20

ns (min)

t

Rising Edge of SYSCLK number 1 to Data

Valid

With 8.33 MHz

SYSCLK

360

ns (max)

DS100036-5

The delay between consecutive IORD and IOWR pulses should be greater than 50 ns to ensure that a Power-on reset does not

occur unintentionally. (See

Section 3.2 ‘Resets’ )

FIGURE 2. ISA Bus Read Timing Diagram

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