HD643303x Hitachi, HD643303x Datasheet - Page 102

• Manufacturer Part Number: HD643303x
• Description: Hitachi Microcomputer
• Manufacturer: Hitachi

5.2.5 IRQ Sense Control Register (ISCR)
ISCR is an 8-bit readable/writable register that selects level sensing or falling-edge sensing of the
inputs at pins IRQ
ISCR is initialized to H'00 by a reset and in hardware standby mode.
Bits 7 to 5—Reserved: These bits can be written and read, but they do not select level or falling-
edge sensing.
Bits 4 to 0—IRQ
interrupts IRQ
sensing.
Bits 4 to 0
IRQ4SC to IRQ0SC Description
0
1
Bit
Initial value
Read/Write
4
to IRQ
4
4
R/W
to IRQ
to IRQ
—
7
0
Interrupts are requested when IRQ
Interrupts are requested by falling-edge input at IRQ
0
are requested by level sensing of pins IRQ
Reserved bit
0
0
.
Sense Control (IRQ4SC to IRQ0SC): These bits selects whether
R/W
—
6
0
R/W
—
5
0
IRQ4SC
87
R/W
IRQ to IRQ sense control
These bits select level sensing or falling-edge
sensing for IRQ
4
0
4
4
IRQ3SC
to IRQ
R/W
3
0
0
0
4
inputs are low
4
IRQ2SC
to IRQ
to IRQ
R/W
2
0
0
4
0
interrupts
to IRQ
, or by falling-edge
IRQ1SC
R/W
1
0
0
(Initial value)
IRQ0SC
R/W
0
0