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Table 4-24. gafr0_l bit definitions, Table 4-25. gafr0_u bit definitions – Intel PXA26X User Manual

Page 126

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4-18

Intel® PXA26x Processor Family Developer’s Manual

System Integration Unit

“00” indicates normal GPIO function for GPIO[85:0]. Indicates default dedicated functionality
for GPIO[89:86].

“01” selects alternate input function 1 (ALT_FN_1_IN) or alternate output function 1
(ALT_FN_1_OUT) for GPIO[85:0]. Selects GPIO function for GPIO[89:86].

“10” selects alternate input function 2 (ALT_FN_2_IN) or alternate output function 2
(ALT_FN_2_OUT)

“11” selects alternate input function 3 (ALT_FN_3_IN) or alternate output function 3
(ALT_FN_3_OUT)

Warning:

Configuring a GPIO to map to an alternate function that is not available causes indeterminate
results.

Table 4-24. GAFR0_L Bit Definitions

Physical Address

0x40E0_0054

GAFR0_L

System Integration Unit

Bit

31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9

8

7

6

5

4

3

2

1

0

AF15

AF14

AF13

AF12

AF11

AF10

AF9

AF8

AF7

AF6

AF5

AF4

AF3

AF2

AF1

AF0

Reset

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Bits

Name

Description

<31:0>

AF[x]

GPIO PIN ‘X’ ALTERNATE FUNCTION SELECT BITS (where x = 0 through 15):

A bit-pair in this register determines the corresponding GPIO pin’s functionality as one of
the alternate functions that is mapped to it or as a generic GPIO pin.

00 – The corresponding GPIO pin (GPIO[x]) is used as a general purpose I/O.

01 – The corresponding GPIO pin (GPIO[x]) is used for its alternate function 1.

10 – The corresponding GPIO pin (GPIO[x]) is used for its alternate function 2.

11 – The corresponding GPIO pin (GPIO[x]) is used for its alternate function 3.

Table 4-25. GAFR0_U Bit Definitions

Physical Address

0x40E0_0058

GAFR0_U

System Integration Unit

Bit

31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9

8

7

6

5

4

3

2

1

0

AF31

AF30

AF29

AF28

AF27

AF26

AF25

AF24

AF23

AF22

AF21

AF20

AF19

AF18

AF17

AF16

Reset

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Bits

Name

Description

<31:0>

AF[x]

GPIO PIN ‘X’ ALTERNATE FUNCTION SELECT BITS (where x = 16 through 31):

A bit-pair in this register determines the corresponding GPIO pin’s functionality as one of
the alternate functions that is mapped to it or as a generic GPIO pin.

00 – The corresponding GPIO pin (GPIO[x]) is used as a general purpose I/O.

01 – The corresponding GPIO pin (GPIO[x]) is used for its alternate function 1.

10 – The corresponding GPIO pin (GPIO[x]) is used for its alternate function 2.

11 – The corresponding GPIO pin (GPIO[x]) is used for its alternate function 3.