CHAPTER 4 PORT FUNCTIONS
(f) External interrupt rising edge specification register 0 (INTR0)
This is an 8-bit register that specifies the rising edge as the detection edge for the external interrupt pin.
This register can be read/written in 8-bit or 1-bit units.
Caution When switching from the external interrupt function (alternate function) to the port
function, edge detection may be performed. Therefore, set the port mode after setting
INTF0n bit = INTR0n bit = 0.
After Reset: 00H
R/W
Address: FFFFFC20H
INTR0
0
INTR06 INTR05 INTR04 INTR03 INTR02
0
0
Remark For specification of the valid edge, refer to Table 4-5.
Table 4-5. Valid Edge Specification
INTF0n
INTR0n
Valid edge specification (n = 2 to 6)
0
0
1
1
0
1
0
1
No edge detection
Rising edge
Falling edge
Both edges
Remark n = 2: Control of NMI pin
n = 3 to 6: Control of INTP0 to INTP3 pins
User’s Manual U15862EJ3V0UD
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NEC [ NEC ]
