CHAPTER 4 PORT FUNCTIONS
(d) Pull-up resistor option register 0 (PU0)
This is an 8-bit register that specifies the connection of an on-chip pull-up resistor.
This register can be read/written in 8-bit or 1-bit units.
After Reset: 00H
R/W
Address: FFFFFC40H
PU0
0
PU06
PU05
PU04
PU03
PU02
PU01
PU00
PU0n
Control of on-chip pull-up resistor connection (n = 0 to 6)
0
1
Not connected
Connected
(e) External interrupt falling edge specification register 0 (INTF0)
This is an 8-bit register that specifies the falling 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: FFFFFC00H
INTF0
0
INTF06 INTF05 INTF04 INTF03 INTF02
0
0
Remark For specification of the valid edge, refer to Table 4-5.
User’s Manual U15862EJ3V0UD
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NEC [ NEC ]
