Adc clock configuration register, Adc output registers 0-7 – Digi NS9215 User Manual

Page 477

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A N A L O G - T O - D I G I T A L C O N V E R T E R ( A D C ) M O D U L E

ADC Clock Configuration register

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477

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A D C C l o c k C o n f i g u r a t i o n r e g i s t e r

Address: 9003_9004

The ADC Clock Configuration register controls the ADC clock generator. The source
clock is the output of the PLL. The maximum ADC clock frequency is 14 MHz and the
conversion time is 14 clock cycles. This is the formula for the ADC clock:

ADC clock = PLL clock / (2 x (N+1))

Example

PLL clock frequency = 299.8272 MHz

N value = 10

ADC clock frequency:

ADC clock = 299.8272 MHz / (2 x (10+1)) = 13.6285 MHz

Wait states can be added to increase conversion time beyond 14 clock cycles.

Register

Register bit
assignment

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A D C O u t p u t R e g i s t e r s 0 - 7

Addresses: 9003_9008 / 9003_900C / 9003_9010 / 9003_9014 / 9003_9018 /
9003_901C / 9003_9020 / 9003_9024

The ADC Output registers provide CPU access for the ADC output for each channel.

13

12

11

10

9

8

7

6

5

4

3

2

1

0

15

14

31

29

28

27

26

25

24

23

22

21

20

19

18

17

16

30

WAIT

N

Not used

Bit(s)

Access

Mnemonic

Reset

Description

D31:16

R/W

WAIT

N/A

Number of additional clock cycles per conversion
cycle.

D15:10

R/W

Not used

0

This field must be written to 0.

D09:00

R/W

N

0

ADC clock converter.

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