Nxp Semiconductors UM10237 ユーザーズマニュアル

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UM10237_2
© NXP B.V. 2008. All rights reserved.
User manual
Rev. 02 — 19 December 2008 
177 of 792
NXP Semiconductors
UM10237
Chapter 9: LPC24XX Pin connect
3.
Pin function select register values
The PINSEL registers control the functions of device pins as shown below. Pairs of bits in 
these registers correspond to specific device pins.
 
The direction control bit in the GPIO registers is effective only when the GPIO function is 
selected for a pin. For other functions, direction is controlled automatically. Each 
derivative typically has a different pinout and therefore a different set of functions possible 
for each pin. Details for a specific derivative may be found in the appropriate data sheet.
4.
Pin mode select register values
The PINMODE registers control the on-chip pull-up/pull-down resistor feature for all GPIO 
ports. Two bits are used to control a port pin. PINMODEn register bits are reserved for not 
available pins, e.g. pins P2[15:14] are not available on LPC2458 and are reserved in 
PINSEL5 and PINMODE5.
 
5.
Register description
The Pin Control Module contains 12 registers as shown in 
 below.
Remark: The LCD pins in the PINSEL registers are available on the LPC247x only.
 
Table 127. Pin function select register bits
PINSEL0 to 
PINSEL9 Values
Function
Value after Reset
00
Primary (default) function, typically GPIO port
00
01
First alternate function
10
Second alternate function
11
Third alternate function
Table 128. Pin Mode Select register bits
PINMODE0 to 
PINMODE9 
Values
Function
Value after Reset
00
Pin has an on-chip pull-up resistor enabled.
00
01
Reserved. This value should not be used.
10
Pin has neither pull-up nor pull-down resistor enabled.
11
Pin has an on-chip pull-down resistor enabled.
Table 129. Summary of pin connect block registers
Name
Description
Access Reset Value
Address
PINSEL0
Pin function select register 0
R/W
0x0000 0000
0xE002 C000
PINSEL1
Pin function select register 1
R/W
0x0000 0000
0xE002 C004
PINSEL2
Pin function select register 2
R/W
0x0000 0000
0xE002 C008
PINSEL3
Pin function select register 3
R/W
0x0000 0000
0xE002 C00C
PINSEL4
Pin function select register 4
R/W
0x0000 0000
0xE002 C010
PINSEL5
Pin function select register 5
R/W
0x0000 0000
0xE002 C014