
3.3 Control registers
APPENDIX
3820 GROUP USER’S MANUAL
3–27
Fig. 3.3.19 Structure of interrupt request register 2
Fig. 3.3.18 Structure of interrupt request register 1
b7b6 b5b4b3 b2b1b0
Interrupt request register 2 (IREQ2) [Address 3D
16
]
B
0
Name
Functions
At reset R W
0
Interrupt request register 2
CNTR
0
interrupt
request bit
CNTR
1
interrupt
request bit
Timer 1 interrupt
request bit
INT
2
interrupt
request bit
INT
3
interrupt
request bit
Key input interrupt
request bit
Serial I/O2
interrupt request bit
Nothing is allocated. This bit cannot be written to
and is fixed to “0” at reading.
0 : No interrupt request issued
1 : Interrupt request issued
0 : No interrupt request issued
1 : Interrupt request issued
0 : No interrupt request issued
1 : Interrupt request issued
0 : No interrupt request issued
1 : Interrupt request issued
0 : No interrupt request issued
1 : Interrupt request issued
0 : No interrupt request issued
1 : Interrupt request issued
0 : No interrupt request issued
1 : Interrupt request issued
1
0
2
0
3
0
8
:
“0” can be set by software, but “1” cannot be set.
4
0
5
0
6
0
7
0
8
×
8
8
8
8
8
8
0
b7b6 b5b4b3 b2b1b0
Interrupt request register 1 (IREQ1) [Address 3C
16
]
B
0
Name
Functions
At reset R W
0
Interrupt request register 1
0 : No interrupt request issued
1 : Interrupt request issued
0 : No interrupt request issued
1 : Interrupt request issued
0 : No interrupt request issued
1 : Interrupt request issued
0 : No interrupt request issued
1 : Interrupt request issued
0 : No interrupt request issued
1 : Interrupt request issued
0 : No interrupt request issued
1 : Interrupt request issued
0 : No interrupt request issued
1 : Interrupt request issued
0 : No interrupt request issued
1 : Interrupt request issued
8
INT
0
interrupt request
bit
INT
1
interrupt request
bit
Serial I/O receive
interrupt request bit
Serial I/O transmit
interrupt request bit
Timer X interrupt
request bit
Timer Y interrupt
request bit
Timer 2 interrupt
request bit
Timer 3 interrupt
request bit
1
0
2
0
3
0
8
:
“0” is set by software, but not “1.”
4
0
5
0
6
0
7
0
8
8
8
8
8
8
8