Intel® PXA255 Processor Developer’s Manual
4-17
System Integration Unit
Caution:
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.
Содержание PXA255
Страница 1: ...Intel PXA255 Processor Developer s Manual January 2004 Order Number 278693 002 ...
Страница 24: ...xxiv Intel PXA255 Processor Developer s Manual Contents ...
Страница 30: ...1 6 Intel PXA255 Processor Developer s Manual Introduction ...
Страница 310: ...7 46 Intel PXA255 Processor Developer s Manual LCD Controller ...
Страница 330: ...8 20 Intel PXA255 Processor Developer s Manual Synchronous Serial Port Controller ...
Страница 358: ...9 28 Intel PXA255 Processor Developer s Manual I2 C Bus Interface Unit ...
Страница 488: ...13 36 Intel PXA255 Processor Developer s Manual AC 97 Controller Unit ...
Страница 572: ...16 30 Intel PXA255 Processor Developer s Manual Network SSP Serial Port ...
Страница 599: ...Intel PXA255 Processor Developer s Manual 17 27 Hardware UART ...
Страница 600: ......