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Chapter 4
Port Functions
User’s Manual U16702EE3V2UD00
(j) External interrupt rising edge specification register 3 (INTR3)
This is an 8-bit register used to specify detection of the rising edge for the external interrupt pin.
This register can be read and written only in 16-bit units.
Cautions: 1. When switching from the external interrupt function (alternate function) to the
port function, edge detection may occur. Therefore, set the port mode after set-
ting INTF3 = INTR3 bit = 0.
2. An on-chip circuit for eliminating noise through analog delay is provided for
external interrupt input.
Figure 4-28:
External Interrupt Rising Edge Specification Register 3 (INTR3) Format
Remark:
For details on valid edge specification, refer to Table 4-6.
Symbol
7
6
5
4
3
2
1
0
Address
After reset
INTR3
INTR37
0
0
0
0
0
INTR31
0
FFFFFC26H
0000H
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Table 4-6:
Valid Edge Specification
INTF3n
INTR3n
Valid Edge Specification (n = 1, 7)
0
0
No edge specified
0
1
Rising edge
1
0
Falling edge
1
1
Both edges
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