4513_03 Datasheet, PDF (41/210 Pages) Renesas Technology Corp – 4-BIT SINGLE-CHIP MICROCOMPUTER

HARDWARE
FUNCTION BLOCK OPERATIONS
(3) External interrupt control registers
• Interrupt control register I1
Register I1 controls the valid waveform for the external 0 inter-
rupt. Set the contents of this register through register A with the
TI1A instruction. The TAI1 instruction can be used to transfer the
contents of register I1 to register A.
• Interrupt control register I2
Register I2 controls the valid waveform for the external 1 inter-
rupt. Set the contents of this register through register A with the
TI2A instruction. The TAI2 instruction can be used to transfer the
contents of register I2 to register A.
Table 8 External interrupt control registers
Interrupt control register I1
I13
Not used
Interrupt valid waveform for INT0 pin/
I1 2
return level selection bit (Note 2)
I11
INT0 pin edge detection circuit control bit
INT0 pin
I10
timer 1 control enable bit
at reset : 00002
at RAM back-up : state retained
R/W
0
This bit has no function, but read/write is enabled.
1
Falling waveform (“L” level of INT0 pin is recognized with the SNZI0
0
instruction)/“L” level
Rising waveform (“H” level of INT0 pin is recognized with the SNZI0
1
instruction)/“H” level
0
One-sided edge detected
1
Both edges detected
0
Disabled
1
Enabled
Interrupt control register I2
at reset : 00002
at RAM back-up : state retained
R/W
I23
Not used
0
This bit has no function, but read/write is enabled.
1
Interrupt valid waveform for INT1 pin/
I22
return level selection bit (Note 3)
Falling waveform (“L” level of INT1 pin is recognized with the SNZI1
0
instruction)/“L” level
Rising waveform (“H” level of INT1 pin is recognized with the SNZI1
1
instruction)/“H” level
I21
INT1 pin edge detection circuit control bit
0
One-sided edge detected
1
Both edges detected
INT1 pin
I20
timer 3 control enable bit
0
Disabled
1
Enabled
Notes 1: “R” represents read enabled, and “W” represents write enabled.
2: When the contents of I12 is changed, the external interrupt request flag EXF0 may be set. Accordingly, clear EXF0 flag with the SNZ0 instruction.
3: When the contents of I22 is changed, the external interrupt request flag EXF1 may be set. Accordingly, clear EXF1 flag with the SNZ1 instruction.
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4513/4514 Group User’s Manual