3 smc cycle register – Rainbow Electronics AT91CAP9S250A User Manual

Page 208

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208

6264A–CAP–21-May-07

AT91CAP9S500A/AT91CAP9S250A

22.14.3

SMC Cycle Register

Register Name:

SMC_CYCLE[0..

5

]

Access Type:

Read/Write

• NWE_CYCLE: Total Write Cycle Length

The total write cycle length is the total duration in clock cycles of the write cycle. It is equal to the sum of the setup, pulse
and hold steps of the NWE and NCS signals. It is defined as:

Write cycle length = (NWE_CYCLE[8:7]*256 + NWE_CYCLE[6:0]) clock cycles

• NRD_CYCLE: Total Read Cycle Length

The total read cycle length is the total duration in clock cycles of the read cycle. It is equal to the sum of the setup, pulse
and hold steps of the NRD and NCS signals. It is defined as:

Read cycle length = (NRD_CYCLE[8:7]*256 + NRD_CYCLE[6:0]) clock cycles

31

30

29

28

27

26

25

24

NRD_CYCLE

23

22

21

20

19

18

17

16

NRD_CYCLE

15

14

13

12

11

10

9

8

NWE_CYCLE

7

6

5

4

3

2

1

0

NWE_CYCLE

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