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CHAPTER 19 INTERRUPT FUNCTIONS
(1) Interrupt request flag registers (IF0L, IF0H, IF1L)
The interrupt request flags are set to 1 when the corresponding interrupt request is generated or an instruction
is executed. They are cleared to 0 when an instruction is executed upon acknowledgment of an interrupt request
or upon application of RESET input.
IF0L, IF0H, and IF1L are set by a 1-bit or 8-bit memory manipulation instruction. When IF0L and IF0H are
combined to form 16-bit register IF0, they are read with a 16-bit memory manipulation instruction.
RESET input sets these registers to 00H.
Figure 19-2. Interrupt Request Flag Register (IF0L, IF0H, IF1L) Format
Address: FFE0H After Reset: 00H R/W
Symbol
7
6
5
4
3
2
1
0
IF0L
STIF0
SRIF0
SERIF0
PIF3
PIF2
PIF1
PIF0
WDTIF
Address: FFE1H After Reset: 00H R/W
Symbol
7
6
5
4
3
2
1
0
IF0H
TMIF51
TMIF50
TMIF01
TMIF00
WTIIF
IICIF0
Note 1
CSIIF31
Note 2
CSIIF30
Address: FFE2H After Reset: 00H R/W
Symbol
7
6
5
4
3
2
1
0
IF1L
0
0
0
0
0
KRIF
WTIF
ADIF0
XXIFX
Interrupt Request Flag
0
No interrupt request signal is generated
1
Interrupt request is generated, interrupt request status
Notes 1.
Incorporated only in the
μ
PD780024 and 780034 Subseries. Be sure to set 0 for the
μ
PD780024Y,
780034Y Subseries.
2.
Incorporated only in the
μ
PD780024Y, 780034Y Subseries. Be sure to set 0 for the
μ
PD780024,
780034 Subseries.
Cautions 1. The WDTIF flag is R/W enabled only when the watchdog timer is used as the interval timer.
If watchdog timer mode 1 is used, set the WDTIF flag to 0.
2. Be sure to set 0 to IF1L bits 3 to 7.
3. When operating a timer, serial interface, or A/D converter after stand-by release, run it once
after clearing an interrupt request flag. An interrupt request flag may be set by noise.