SN74ACT7200L, SN74ACT7201LA, SN74ACT7202LA

256

× 9, 512 × 9, 1024 × 9

ASYNCHRONOUS FIRST-IN, FIRST-OUT MEMORIES

SCAS221A – FEBRUARY 1993 – REVISED SEPTEMBER 1995

11

POST OFFICE BOX 655303

PARAMETER MEASUREMENT INFORMATION

R

EF

W

tpd(R-E)

tpd(W-E)

Last Read

Ignored

Read

First Write

Additional Writes

Valid

D0 – D8

ta

Figure 3. Empty-Flag Waveforms

FL /RT

tc(RT)

tw(RT)

tsu(RT)

th(RT)

W, R

tpd(RT-FL)

XO/HF, EF, FF

Valid Flag

NOTE A: The EF, FF, and XO/HF status flags are valid after completion of the retransmit cycle.

Figure 4. Retransmit Waveforms