M16C / 62A Group (80-pin)
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
There are two kinds of resets; hardware and software. In both cases, operation is the same after the reset.
(See “Software Reset” for details of software resets.) This section explains on hardware resets.
When the supply voltage is in the range where operation is guaranteed, a reset is effected by holding the
reset pin level “L” (0.2VCC max.) for at least 20 cycles. When the reset pin level is then returned to the “H”
level while main clock is stable, the reset status is cancelled and program execution resumes from the
address in the reset vector table.
The RAM is undefined at power on. The initial values must therfore be set. When a reset signal is applied
while the CPU is writing a value to the RAM, the value may be set as unknown due to the termination of the
Figure 1.6.1 shows the example reset circuit. Figure 1.6.2 shows the reset sequence.
Example when VCC = 5V.
Figure 1.6.1. Example reset circuit
More than 20 cycles are needed
Content of reset vector
Figure 1.6.2. Reset sequence