136

80C286/883

Waveforms

NOTES:

1. The modified timing is due to the CMDLY signal being active.

2. 82C254 and 82C288 Timing Waveforms are shown for reference only, and no guarantee is inplied.

FIGURE 2. MAJOR CYCLE TIMING

3

1

2

12A

12B

φ2

φ2

φ1

φ2

φ1

φ2

φ1

φ2

φ1

φ2

φ1

CLK

S1 • S0

19

13

19

13

M/IO,

BHE, LOCK

VALID ADDRESS

VALID ADDRESS

13

13

VALID CONTROL

VALID CONTROL

VALID WRITE DATA

9

8

14

11

10

15

11

10

11

12

19

14

13

19

19

20

16

17

12

13

13

12

12

13

29

30

(SEE NOTE 1)

29

30

19

20

21

22

23

24

READ

READ CYCLE

ILLUSTRATED WITH ZERO

WAIT STATES

WRITE CYCLE

ILLUSTRATED WITH ONE

WAIT STATE

READY

SRDY +

ARDY +

PCLK

ALF

CMDLY

MWTC

MRDC

DT/R

ARDYEN

SRDYEN

COD INTA

BUS CYCLE TYPE

DEN

VALID READ DATA