
1-40
Under
Specifications in this manual are tentative and subject to change
Rev. G
Overview of Interrupts
MITSUBISHI MICROCOMPUTERS
M30222 Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Interrupt Control
Descriptions are given here regarding how to enable or disable maskable interrupts and how to set the
priority to be accepted. What is described here does not apply to non-maskable interrupts.
Enable or disable a maskable interrupt using the interrupt enable flag (I flag), interrupt priority level
selection bits, or processor interrupt priority level (IPL). Whether an interrupt request is present or
absent is indicated by the interrupt request bit. The interrupt request bit and the interrupt priority level
selection bit are located in the interrupt control register of each interrupt. Also, the interrupt enable
flag (I flag) and the IPL are located in the CPU flag register (FLG). Figure 1.23 shows the memory map
of the interrupt control registers.
Figure 1.23. Memory map of the interrupt control registers.
INTiIC(i=0 to 1)
INT2IC/SI3IC
INT31C/SI4IC
INT4IC/TA3IC
INT5/TA4IC
INTiIC(i= 6 to 7)
ILVL0
Symbol
Address
When reset
XX000000
2
XX000000
2
XX000000
2
XX000000
2
XX000000
2
XX000000
2
005D
16
, 005E
16
005F
16
0044
16
0058
16
0059
16
0049
16
, 0048
16
Bit name
Function
Bit symbol
W
R
b7
b6
b5
0
b4
b3
b2
b1
b0
IR
POL
Interrupt priority level
select bit
Interrupt request bit
Polarity select bit
Reserved bit
0: Interrupt not requested
1: Interrupt requested
0: Selects falling edge
Selects rising edge
1:
Always set to
“
0
”
ILVL1
ILVL2
Note 1 To rewrite the interrupt control register, do so at a point that does not generate the
interrupt request for that register. For details, see the precautions for interrupts.
Note 2: This bit can only be accessed for reset (= 0), but cannot be accessed for set (= 1).
(Note 2)
Interrupt control register
b7
b6
b5
b4
b3
b2
b1
b0
Bit name
Function
Bit symbol
ILVL0
W
R
TBiSymbol
16
to 0047
16
BCNIC
DMiIC(i=0, 1) 004A
16
, 004C
16
KUPIC
ADIC
SiTIC(i=0 to 2) 0051
16
0053
16
, 004F
16
SiRIC(i=0 to 2) 0052
16
, 0054
16
, 0050
16
TAiIC(i=0 to 2) 0055
16
to 0057
16
TBiIC(i=0 to 2) 005A
16
to 005C
16
Address
When reset
XXXX0000
2
XXXX0000
2
XXXX0000
2
XXXX0000
2
XXXX0000
2
XXXX0000
2
XXXX0000
2
XXXX0000
2
XXXX0000
2
16
004D
16
004E
16
IR
Interrupt priority level
select bit
Interrupt request bit
0 : Interrupt not requested
1 : Interrupt requested
ILVL1
ILVL2
(Note 1)
Note 1: To rewrite the interrupt control register, do so at a point that does not generate the
interrupt request for that register. For details, see the precautions for interrupts.
Note 2: This bit can only be accessed for reset (= 0), but cannot be accessed for set (= 1).
0 0 0 : Level 0 (interrupt disabled)
0 0 1 : Level 1
0 1 0 : Level 2
0 1 1 : Level 3
1 0 0 : Level 4
1 0 1 : Level 5
1 1 0 : Level 6
1 1 1 : Level 7
b2 b1 b0
0 0 0 : Level 0 (interrupt disabled)
0 0 1 : Level 1
0 1 0 : Level 2
0 1 1 : Level 3
1 0 0 : Level 4
1 0 1 : Level 5
1 1 0 : Level 6
1 1 1 : Level 7
b2 b1 b0
(Note 2)
Nothing is assigned.
Write "0" when writing to these bits. If read, the value is "0".
Nothing is assigned.
Write "0" when writing to these bits. If read, the value is "0".