GMS90C320

34

OCT. 2000 Ver 1.2

AC Characteristics for 50MHz version

External Program Memory Characteristics

Parameter

Symbol

50 MHz Oscillator

Variable Oscillator

Unit

Min.

Max.

Min.

Max.

ALE pulse width

25

-

-

ns

Address setup to ALE

5-

-

ns

Address hold after ALE

5-

-

ns

ALE low to valid instruction in

-40

-

ns

ALE to PSEN

5-

-

ns

PSEN pulse width

45

-

-

ns

PSEN to valid instruction in

-20

-

ns

Input instruction hold after PSEN

0-

0

-

ns

Input instruction float after PSEN

1)

Interfacing the GMS90C320 to devices with float times up to 20 ns is permissible. This limited bus contention will not cause any damage

to port 0 Drivers.

-10

-

ns

Address valid after PSEN

15

-

ns

Address to valid instruction in

-45

-

ns

Address float to PSEN

-5

-

-5

-

ns