HD643303x Hitachi, HD643303x Datasheet - Page 101

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

5.2.4 IRQ Enable Register (IER)
IER is an 8-bit readable/writable register that enables or disables IRQ
IER 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 enable or disable
interrupts.
Bits 4 to 0—IRQ
IRQ
Bits 4 to 0
IRQ4E to IRQ0E
0
1
Bit
Initial value
Read/Write
0
interrupts.
4
R/W
to IRQ
Description
IRQ
IRQ
—
7
0
4
4
Reserved bits
to IRQ
to IRQ
0
Enable (IRQ7E to IRQ0E): These bits enable or disable IRQ
R/W
—
6
0
0
0
interrupts are disabled
interrupts are enabled
R/W
—
5
0
86
IRQ4E
R/W
4
0
IRQ3E
R/W
3
0
IRQ to IRQ enable
These bits enable or disable
IRQ
4
4
to IRQ
IRQ2E
0
R/W
to IRQ
2
0
0
0
interrupts
4
IRQ1E
R/W
interrupt requests.
1
0
(Initial value)
IRQ0E
R/W
0
0
4
to