
CHAPTER 4 PORT FUNCTIONS
User’s Manual U15905EJ2V1UD
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(h) External interrupt rising edge specification register 9 (INTR9)
This 16-bit register specifies detection of the rising edge of the external interrupt pins.
It can be read or written only in 16-bit units. If the higher 8 bits of the INTR9 register are used as INTR9H
and the lower 8 bits as INTR9L, however, INTR9H and INTR9L can be manipulated in 8-bit or 1-bit units.
Caution
Set the port mode after clearing the INTF9n and INTR9n bits to 0 when switching from the
external interrupt function (alternate function) to the port function because an edge may
be detected.
INTR9
(INTR9L)
After reset: 0000H
R/W
Address: INTR9 FFFFFC32H, INTR9L FFFFFC32H
0
INTR93
INTR92
0
00
0
8
9
10
11
12
13
14
15
Remark
For how to specify a valid edge, refer to Table 4-11.
Table 4-11. Specifying Valid Edge
INTF9n
INTR9n
Specifies valid edge (n = 2 or 3).
0
Detects no edge.
0
1
Rising edge
1
0
Falling edge
1
Both edges
Caution
When INTP5 and INTP6 are not used, be sure to clear INTF9n and INTR9n to “00”.
Remark
n = 2 or 3: Control of INTP5 or INTP6 pin