
M306V2ME-XXXFP
M306V2EEFP
MITSUBISHI MICROCOMPUTERS
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER with CLOSED CAPTION DECODER
and ON-SCREEN DISPLAY CONTROLLER
18
Rev. 1.0
2.3 Reset
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” (0.2V
CC
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.
Figure 2.3.1 shows the example reset circuit. Figure 2.3.2 shows the reset sequence.
Figure 2.3.1 Example reset circuit
RESET
V
CC
0.9V
RESET
V
CC
0V
0V
5V
5V
4.5V
Example when f(X
IN
) = 10 MHz and V
CC
= 5V.
2.3.1 Software Reset
Writing “1” to bit 3 of the processor mode register 0 (address 0004
16
) applies a (software) reset to the
microcomputer. A software reset has almost the same effect as a hardware reset. The contents of internal
RAM are preserved.