M30220 Datasheet, PDF (12/212 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

Unddeevrelopment
Preliminary Specifications REV.E
Mitsubishi microcomputers
Specifications in this manual are tentative and subject to change.
M30220 Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Reset
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” (0.2VCC 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.
Figure 1.6.1 shows the example reset circuit. Figure 1.6.2 shows the reset sequence.
RESET
VCC
5V
VCC
0V
5V
RESET
0V
4.0V
0.8V
Figure 1.6.1. Example reset circuit
XIN
RESET
BCLK
Address
(Internal Address signal)
More than 20 cycles are needed
BCLK 24 cycles
FFFFC16
FFFFE16
Content of reset vector
Figure 1.6.2. Reset sequence
____________
Table 1.6.1 shows the statuses of the other pins while the RESET pin level is “L”. Figures 1.6.3 and 1.6.4
show the internal status of the microcomputer immediately after the reset is cancelled.
____________
Table 1.6.1. Pin status when RESET pin level is “L”
Pin name
Status
P0, P10 to P12
P1 to P9, P13
SEG0 to SEG15
COM0 to COM3
Input port(with a pull up resistor)
Input port (floating)
“H” level is output
“H” level is output
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