hd66100 Renesas Electronics Corporation., hd66100 Datasheet - Page 87

• Manufacturer Part Number: hd66100
• Description: H8/3867 Series
• Manufacturer: Renesas Electronics Corporation.

4. Interrupt request register 1 (IRR1)
IRR1 is an 8-bit read/write register, in which a corresponding flag is set to 1 when a timer A or
IRQ
accepted. It is necessary to write 0 to clear each flag.
Bit 7: Timer A interrupt request flag (IRRTA)
Bit 7
IRRTA
0
1
Bit 6: Reserved bit
Bit 6 is a readable/writable reserved bit. It is initialized to 0 by a reset.
Bit 5: Reserved bit
Bit 5 is reserved; it is always read as 1 and cannot be modified.
Bits 4 to 0: IRQ
Bit n
IRRIn
0
1
72
Bit
Initial value
Read/Write
Note: * Only a write of 0 for flag clearing is possible
4
to IRQ
0
Description
Clearing conditions:
When IRRTA = 1, it is cleared by writing 0
Setting conditions:
When the timer A counter value overflows from H'FF to H'00
Description
Clearing conditions:
When IRRIn = 1, it is cleared by writing 0
Setting conditions:
When pin IRQn is designated for interrupt input and the designated signal edge is
input
interrupt is requested. The flags are not cleared automatically when an interrupt is
4
to IRQ
IRRTA
R/W
7
0
*
0
interrupt request flags (IRRI4 to IRRI0)
R/W
—
6
0
*
—
—
5
1
IRRI4
R/W
4
0
*
IRRI3
R/W
3
0
*
IRRI2
R/W
2
0
*
IRRI1
R/W
1
0
*
(initial value)
(initial value)
(n = 4 to 0)
IRRI0
R/W
0
0
*