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Pio enable register, Pio disable register – Rainbow Electronics AT75C220 User Manual

Page 67

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AT75C220

67

PIO Enable Register

Register Name:PIO_PER
Access Type:Write-only

This register is used to enable individual pins to be controlled by the PIO controller instead of the associated peripheral.
When the PIO is enabled, the associated peripheral (if any) is held at logic zero.

1 = Enables the PIO to control the corresponding pin (disables peripheral control of the pin).

0 = No effect.

PIO Disable Register

Register Name: PIO_PDR
Access Type:Write-only

This register is used to disable PIO control of individual pins. When the PIO control is disabled, the normal peripheral func-
tion is enabled on the corresponding pin.

1 = Disables PIO control (enables peripheral control) on the corresponding pin.

0 = No effect.

31

30

29

28

27

26

25

24

P31

P30

P29

P28

P27

P26

P25

P24

23

22

21

20

19

18

17

16

P23

P22

P21

P20

P19

P18

P17

P16

15

14

13

12

11

10

9

8

P15

P14

P13

P12

P11

P10

P9

P8

7

6

5

4

3

2

1

0

P7

P6

P5

P4

P3

P2

P1

P0

31

30

29

28

27

26

25

24

P31

P30

P29

P28

P27

P26

P25

P24

23

22

21

20

19

18

17

16

P23

P22

P21

P20

P19

P18

P17

P16

15

14

13

12

11

10

9

8

P15

P14

P13

P12

P11

P10

P9

P8

7

6

5

4

3

2

1

0

P7

P6

P5

P4

P3

P2

P1

P0