deveopmen
Interrupts
Rev.B2 for proof reading
Mitsubishi Microcomputers
M32C/83 group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
91
Symbol
Address
When reset
XX00 X000
2
XX00 X000
2
INTiIC(i=0 to 2)
INTiIC(i=3 to 5)(*1)
009E
16
, 007E
16
, 009C
16
007C
16
, 009A
16
, 007A
16
Bit name
Function
Bit symbol
ILVL0
W
R
b7
b6
b5 b4
b3
b2
b1
b0
AA
A
AA
IR
POL
Nothing is assigned.
When write, set "0". When read, their contents are indeterminate.
Interrupt priority level
select bit
Interrupt request bit
Polarity select bit
Level sense/edge
sense select bit
0: Interrupt not requested
1: Interrupt requested
0 : Selects falling edge or L level
1 : Selects rising edge or H level
ILVL1
ILVL2
Note 1: This bit can only be accessed for reset (= 0), but cannot be accessed for set (= 1).
Note 2: When related bit of external interrupt cause select register (address 031F
16
) are used for both edge,
select the falling edge (=0).
Note 3: When level sense is selected, set related bit of external interrupt cause select register (address 031F
16
) to
one edge.
*1 When using 16-bit data bus width in microprocessor mode or memory expansion mode, INT3 to INT5 are used
for data bus. In this case, set the interrupt disabled to INT3IC, INT4IC and INT5IC.
(Note 1)
Interrupt control register
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
AA
A
A
AA
AA
A
A
AA
AA
0 : Edge sense
1 : Level sense
LVS
(Note 2)
(Note 3)
Figure 1.9.4. Interrupt control register (2)
Bit 0 to 2: Interrupt Priority Level Select Bits (ILVL0 to ILVL2)
Interrupt priority levels are set by ILVL0 to ILVL2 bits. When an interrupt request is generated, the
interrupt priority level of this interrupt is compared with IPL. This interrupt is enabled only when its
interrupt priority level is greater than IPL. This means that you can disable any particular interrupt by
setting its interrupt priority level to 0.
Bit 3: Interrupt Request Bit (IR)
This bit is set (= 1) by hardware when an interrupt request is generated. The bit is cleared (= 0) by
hardware when the interrupt request is acknowledged and jump to the interrupt vector.
This bit can be cleared (= 0) (but never be set to 1) in software.