© Koninklijke Philips Electronics N.V. 2006. All rights reserved.
User manual
Rev. 01 — 12 January 2006
21
Philips Semiconductors
UM10161
Volume 1
Chapter 3: System control block
3.5.4 External
Interrupt
Mode
register (EXTMODE - 0xE01F C148)
The bits in this register select whether each EINT pin is level- or edge-sensitive. Only pins
that are selected for the EINT function (see
) and enabled via the
) can cause interrupts from the
External Interrupt function (though of course pins selected for other functions may cause
interrupts from those functions).
Note: Software should only change a bit in this register when its interrupt is
disabled in the VICIntEnable register, and should write the corresponding 1 to the
EXTINT register before enabling (initializing) or re-enabling the interrupt, to clear
the EXTINT bit that could be set by changing the mode.
3.5.5 External
Interrupt
Polarity register (EXTPOLAR - 0xE01F C14C)
In level-sensitive mode, the bits in this register select whether the corresponding pin is
high- or low-active. In edge-sensitive mode, they select whether the pin is rising- or
falling-edge sensitive. Only pins that are selected for the EINT function (see
) and enabled in the VICIntEnable register (see
) can
cause interrupts from the External Interrupt function (though of course pins selected for
other functions may cause interrupts from those functions).
Note: Software should only change a bit in this register when its interrupt is
disabled in the VICIntEnable register, and should write the corresponding 1 to the
EXTINT register before enabling (initializing) or re-enabling the interrupt, to clear
the EXTINT bit that could be set by changing the polarity.
2
EXTWAKE2
When one, assertion of EINT2 will wake up the processor from
Power-down mode.
0
14:3
-
Reserved, user software should not write ones to reserved bits.
The value read from a reserved bit is not defined.
NA
15
RTCWAKE
When one, assertion of an RTC interrupt will wake up the
processor from Power-down mode.
0
Table 10:
Interrupt Wake-up register (INTWAKE - address 0xE01F C144) bit description
Bit
Symbol
Description
Reset
value
Table 11:
External Interrupt Mode register (EXTMODE - address 0xE01F C148) bit
description
Bit
Symbol
Value
Description
Reset
value
0
EXTMODE0 0
Level-sensitivity is selected for EINT0.
0
1
EINT0 is edge sensitive.
1
EXTMODE1 0
Level-sensitivity is selected for EINT1.
0
1
EINT1 is edge sensitive.
2
EXTMODE2 0
Level-sensitivity is selected for EINT2.
0
1
EINT2 is edge sensitive.
7:3
-
-
Reserved, user software should not write ones to reserved
bits. The value read from a reserved bit is not defined.
NA