MITSUBISHI MICROCOMPUTERS
M37735S4LHP
16-BIT CMOS MICROCOMPUTER
RESET CIRCUIT
input voltage must be 0.55 V or less when the power source voltage
reaches 2.7 V. If a resonator/oscillator is connected to the main-clock
oscillation circuit, change the reset input voltage from “L” to “H” after
the main-clock oscillation is fully stabilized.
_____
The microcomputer is released from the reset state when the RESET
pin is returned to “H” level after holding it at “L” level with the power
source voltage at 2.7 to 5.5 V. Program execution starts at the address
formed by setting address A23 – A16 to 0016, A15 – A8 to the contents
of address FFFF16, and A7 – A0 to the contents of address FFFE16.
Figure 13 shows an example of a reset circuit. If the stabilized clock
is input from the external to the main-clock oscillation circuit, the reset
Figure 12 shows the status of the internal registers during reset.
Address
Address
0016
(6116
)
•••
0
Port P0 direction register
Port P1 direction register
Port P2 direction register
Port P3 direction register
Port P4 direction register
Port P5 direction register
Port P6 direction register
Port P7 direction register
Port P8 direction register
A-D control register 0
(0416
(0516
(0816
(0916
)
)
)
)
•••
Watchdog timer frequency selection flag
Waveform output mode register
(6216
(6416
(6816
(6916
)
•••
•••
•••
•••
0
0 0 0
0 0
0016
0016
•••
•••
)
)
)
0
0
0 0 0 0 0
1 0 0 0
UART2 transmit/receive mode register
UART2 transmit/receive control register 0
UART2 transmit/receive control register 1
Oscillation circuit control register 0
Port function control register
0 0 0
0
•••
0 0
0
0
0 0 1 0
0
(0C16
(0D16
)
•••
•••
0016
(6C16
(6D16
)
•••
•••
0 0 0 0
0016
1
)
0016
0016
)
(1016
(1116
(1416
)
•••
•••
•••
(6E16
)
•••
•••
•••
•••
•••
•••
•••
•••
•••
•••
•••
•••
0 0
0016
Serial transmit control register
Oscillation circuit control register 1
A-D/UART2 trans./rece. interrupt control register
UART 0 transmission interrupt control register
UART 0 receive interruupt control register
UART 1 transmission interrupt control register
UART 1 receive interruupt control register
Timer A0 interrupt control register
)
)
(6F16
)
0
0 0 0 0 0
0 0 0 0
0016
(7016
(7116
(7216
(7316
(7416
(7516
(7616
(7716
(7816
(7916
)
0 0 0 0 0 ? ?
?
1
(1E16
(1F16
)
•••
0 0 0 0
)
)
)
)
)
)
)
)
)
0 0 0
0016
1
)
•••
A-D control register 1
0 0 0 0
UART 0 transmit/receive mode register
UART 1 transmit/receive mode register
(3016
(3816
(3416
)
•••
•••
•••
0 0 0 0
)
)
0016
0 0 0 0
0 0 0 0 1 0 0 0
UART 0 transmit/receive
control register 0
UART 1 transmit/receive
control register 0
UART 0 transmit/receive
control register 1
UART 1 transmit/receive
control register 1
0 0 0 0
0 0 0 0 1 0 0 0
(3C16
)
•••
0 0 0 0
0 0 0 0 0 0 1 0
Timer A1 interrupt control register
(3516
)
•••
0 0 0 0
0 0 0 0 0 0 1 0
Timer A2 interrupt control register
(3D16
)
•••
0 0 0 0
(4016
(4216
(4416
(5616
(5716
(5816
(5916
)
•••
0016
Timer A3 interrupt control register
Count start flag
0 0 0 0
)
)
)
)
)
)
•••
•••
0 0 0 0 0
Timer A4 interrupt control register
One- shot start flag
0 0 0 0
0016
Timer B0 interrupt control register
(7A16
(7B16
)
•••
•••
Up-down flag
0 0 0 0
0016
Timer B1 interrupt control register
)
Timer A0 mode register
Timer A1 mode register
Timer A2 mode register
Timer A3 mode register
Timer A4 mode register
Timer B0 mode register
Timer B1 mode register
Timer B2 mode register
Processor mode register 0
Processor mode register 1
Watchdog timer register
•••
•••
0 0 0 0
Timer B2 interrupt control register
0016
(7C16
(7D16
)
•••
•••
0 0 0 0 0 0
0 0 0 0 0 0
0 0 0 0 0 0
•••
•••
0016
0016
INT
INT
INT
0
1
2
interrupt control register
)
interrupt control register
(7E16
(7F16
)
•••
(5A16
(5B16
)
•••
•••
0016
/key input interrupt control register
)
•••
)
0 0 0 ? ? 0 0 0 1 ? ?
0 0 1 0 0 0 0 0
Processor status register (PS)
Program bank register (PG)
0016
Content of FFFF16
Content of FFFE16
000016
(5C16
(5D16
)
)
••• 0 0 1
0 0 0 0
0 0 0 0
••• 0 0 1
•••
Program counter (PC
Program counter (PC
H)
(5E16
(5F16
(6016
)
0016
L)
)
•••
0
Direct page register (DPR)
Data bank register (DT)
)
•••
0016
FFF16
Contents of other registers and RAM are undefined during reset. Initialize them by software.
Fig. 12 Microcomputer internal status during reset
15
RENESAS [ RENESAS TECHNOLOGY CORP ]
