R8C2A Datasheet, PDF (54/609 Pages) Renesas Technology Corp – MCU

R8C/2A Group, R8C/2B Group
5. Resets
5. Resets
The following resets are implemented: hardware reset, power-on reset, voltage monitor 0 reset, voltage monitor 1 reset,
voltage monitor 2 reset, watchdog timer reset, and software reset.
Table 5.1 lists the Reset Names and Sources.
Table 5.1 Reset Names and Sources
Reset Name
Source
Hardware reset
Power-on reset
Voltage monitor 0 reset
Voltage monitor 1 reset
Voltage monitor 2 reset
Watchdog timer reset
Software reset
Input voltage of RESET pin is held “L”
VCC rises
VCC falls (monitor voltage: Vdet0)
VCC falls (monitor voltage: Vdet1)
VCC falls (monitor voltage: Vdet2)
Underflow of watchdog timer
Write 1 to PM03 bit in PM0 register
RESET
VCC
Hardware reset
Power-on reset Power-on reset
circuit
SFRs
Bits VCA25,
VW0C0, and
VW0C6
SFRs
Bits VCA25,
VW0C0, and
VW0C6
Figure 5.1
Voltage
detection
circuit
Watchdog
timer
Voltage monitor 0 reset
Voltage monitor 1 reset
Voltage monitor 2
reset
Watchdog timer
reset
CPU
Software reset
SFRs
Bits VCA13, VCA26, VCA27,
VW1C2, VW1C3,
VW2C2, VW2C3,
VW0C1, VW0F0,
VW0F1, and VW0C7
Pin, CPU, and
SFR bits other than
those listed above
VCA13: Bit in VCA1 register
VCA25, VCA26, VCA27: Bits in VCA2 register
VW0C0, VW0C1, VW0C6, VW0F0, VW0F1, VW0C7: Bits in VW0C register
VW1C2, VW1C3: Bits in VW1C register
VW2C2, VW2C3: Bits in VW2C register
Block Diagram of Reset Circuit
Rev.2.00 Nov 26, 2007 Page 34 of 580
REJ09B0324-0200