Nxp Semiconductors UM10237 ユーザーズマニュアル

UM10237_2

© NXP B.V. 2008. All rights reserved.

 

The System Control Block includes several system features and control registers for a 
number of functions that are not related to specific peripheral devices. These include:

Reset

Brown-Out Detection

External Interrupt Inputs

Miscellaneous System Controls and Status

Code Security vs. Debugging

Each type of function has its own register(s) if any are required and unneeded bits are 
defined as reserved in order to allow future expansion. Unrelated functions never share 
the same register addresses

 shows pins that are associated with system control block functions.

 

All registers, regardless of size, are on word address boundaries. Details of the registers 
appear in the description of each function.

 

EINT0

Input

External Interrupt Input 0 - An active low/high level or 
falling/rising edge general purpose interrupt input. This pin may be 
used to wake up the processor from Idle or Power down modes.

EINT1

Input

External Interrupt Input 1 - See the EINT0 description above.

EINT2

Input

External Interrupt Input 2 - See the EINT0 description above.

EINT3

Input

External Interrupt Input 3 - See the EINT0 description above.

RESET

Input

External Reset input - A LOW on this pin resets the chip, causing 
I/O ports and peripherals to take on their default states, and the 
processor to begin execution at address 0x0000 0000.

EXTINT

External Interrupt Flag Register

R/W

0x00

0xE01F C140

EXTMODE

External Interrupt Mode register

R/W

0x00

0xE01F C148

EXTPOLAR

External Interrupt Polarity Register

R/W

0x00

0xE01F C14C