455A Datasheet, PDF (76/148 Pages) Renesas Technology Corp – SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER

455A Group
CONTROL REGISTERS
Interrupt control register V1
V13 Timer 2 interrupt enable bit
V12 Timer 1 interrupt enable bit
V11 Not used
V10 External 0 interrupt enable bit
at reset : 00002
at power down : 00002
0 Interrupt disabled (SNZT2 instruction is valid)
1 Interrupt enabled (SNZT2 instruction is invalid)
0 Interrupt disabled (SNZT1 instruction is valid)
1 Interrupt enabled (SNZT1 instruction is invalid)
0
This bit has no function, but read/write is enabled.
1
0 Interrupt disabled (SNZ0 instruction is valid)
1 Interrupt enabled (SNZ0 instruction is invalid)
R/W (Note 1)
TAV1/TV1A
Interrupt control register V2
V23 Not used
V22 Not used
V21 Not used
V20 Timer 3 interrupt enable bit
at reset : 00002
at power down : 00002
0
This bit has no function, but read/write is enabled.
1
0
This bit has no function, but read/write is enabled.
1
0
This bit has no function, but read/write is enabled.
1
0 Interrupt disabled (SNZT3 instruction is valid)
1 Interrupt enabled (SNZT3 instruction is invalid)
R/W
TAV2/TV2A
Interrupt control register I1
at reset : 00002
at power down : state retained
R/W
TAI1/TI1A
I13 INT pin input control bit (Note 2)
0 INT pin input disabled
1 INT pin input enabled
I12
Interrupt valid waveform for INT pin/
return level selection bit (Note 2)
0
Falling waveform (“L” level of INT pin is recognized with the SNZI0
instruction)/“L” level
1
Rising waveform (“H” level of INT pin is recognized with the SNZI0
instruction)/“H” level
I11 INT pin edge detection circuit control bit
0 One-sided edge detected
1 Both edges detected
I10
INT pin timer 1 count start synchronous
circuit selection bit
0 Timer 1 count start synchronous circuit not selected
1 Timer 1 count start synchronous circuit selected
Note 1. “R” represents read enabled, and “W” represents write enabled.
Note 2. When the contents of I12 and I13 are changed, the external interrupt request flag (EXF0) may be set.
Rev.1.01 Feb 15, 2008 Page 76 of 146
REJ03B0224-0101