Table of Contents
Advertisement
Wakeup Edge Select Register (WEGR)
Bit
WKEGS7
Initial value
Read/Write
R/W
WEGR is an 8-bit read/write register that specifies rising or falling edge sensing for pins WKPn.
WEGR is initialized to H'00 by a reset.
WKPn Edge Select (WKEGSn)
WKP
WKP
Bit n—WKP
Bit n selects WKPn pin input sensing.
Bit n
WKEGSn
Description
WKPn pin falling edge detected
0
WKPn pin rising edge detected
1
3.3.3
External Interrupts
There are 13 external interrupts: WKP7 to WKP0, IRQ4, IRQ3, IRQ1, IRQ0, and IRQAEC.
Interrupts WKP
to WKP
7
Interrupts WKP7 to WKP0 are requested by either rising or falling edge input to pins WKP
WKP
. When these pins are designated as pins WKP
0
rising or falling edge is input, the corresponding bit in IWPR is set to 1, requesting an interrupt.
Recognition of wakeup interrupt requests can be disabled by clearing the IENWP bit to 0 in
IENR1. These interrupts can all be masked by setting the I bit to 1 in CCR.
When WKP7 to WKP0 interrupt exception handling is initiated, the I bit is set to 1 in CCR.
Vector number 9 is assigned to interrupts WKP7 to WKP0. All eight interrupt sources have the
same vector number, so the interrupt-handling routine must discriminate the interrupt source.
7
6
5
WKEGS6
WKEGS5
0
0
0
R/W
R/W
0
4
3
WKEGS4
WKEGS3
WKEGS2
0
0
R/W
R/W
to WKP
in port mode register 5 and a
7
0
Rev. 6.00, 08/04, page 87 of 628
2
1
WKEGS1
WKEGS0
0
0
R/W
R/W
R/W
(initial value)
(n = 7 to 0)
0
0
to
7
Advertisement
Table of Contents
