M16C26 Datasheet, PDF (65/239 Pages) Renesas Technology Corp – 16-BIT CMOS SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/20 SERIES

Udenvdeelropment
Preliminary Specifications Rev. 0.9
Specifications in this manual are tentative and subject to change.
Interrupts
M16C/26 Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
INT Interrupt
INT0, INT1, INT3 to INT5 are triggered by the edges of external inputs. The edge polarity of the interrupt is
selected using the polarity select bit in the interrupt control registers, 004416, 004816, 004916, 005D16 and
005E16.
To generate interrupts on both rising and falling edges, set the INTi interrupt polarity switching bit of the
interrupt request cause select register (035F16) to "1". Interrupt on both rising and falling edges will be
generated regardless of the value set in the polarity select bit of the corresponding interrupt control regis-
ter.
Figure 1.9.10 shows the Interrupt request cause select register.
Interrupt request cause select register
b7 b6 b5 b4 b3 b2 b1 b0
Symbol
IFSR
Address
035F16
When reset
0016
Bit symbol
IFSR0
IFSR1
IFSR2
Bit name
INT0 interrupt polarity
switching bit
INT1 interrupt polarity
switching bit
Reserved
Function
0 : One edge
1 : Two edges
0 : One edge
1 : Two edges
IFSR3
IFSR4
IFSR5
IFSR6
IFSR7
INT3 interrupt polarity
switching bit
INT4 interrupt polarity
switching bit
INT5 interrupt polarity
switching bit
Interrupt request cause
select bit
Interrupt request cause
select bit
0 : One edge
1 : Two edges
0 : One edge
1 : Two edges
0 : One edge
1 : Two edges
0 : Reserved
1 : INT4 (note)
0 : Reserved
1 : INT5 (note)
Note: To use INTi (i=4,5) functionality, this bit must be set to a 1.
RW
Figure 1.9.10. Interrupt request cause select register
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