M16C Datasheet, PDF (38/262 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

Preliminary Specifications REV.B
Mitsubishi microcomputers
Specifications in this manual are tentative and subject to change.
M16C / 6N Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Clock Generating Circuit
Clock Generating Circuit
The clock generating circuit contains two oscillator circuits that supply the operating clock sources to the
CPU and internal peripheral units.
Table 5-1. Main clock and sub clock generating circuits
Use of clock
Usable oscillator
Pins to connect oscillator
Oscillation stop/restart function
Oscillator status immediately after reset
Other
Main clock generating circuit
Sub clock generating circuit
• CPU’s operating clock source • CPU’s operating clock source
• Internal peripheral units’
• Timer A/B’s count clock
operating clock source
source
Ceramic or crystal oscillator
Crystal oscillator
XIN, XOUT
XCIN, XCOUT
Available
Available
Oscillating
Stopped
Externally derived clock can be input
Example of oscillator circuit
Figure 5-1 shows some examples of the main clock circuit, one using an oscillator connected to the circuit,
and the other one using an externally derived clock for input. Figure 5-2 shows some examples of sub clock
circuits, one using an oscillator connected to the circuit, and the other one using an externally derived clock
for input. Circuit constants in Figures 5-1 and 5-2 vary with each oscillator used. Use the values recom-
mended by the manufacturer of your oscillator.
Microcomputer
(Built-in feedback resistor)
XIN
XOUT
(Note)
Rd
CIN
COUT
Microcomputer
(Built-in feedback resistor)
XIN
XOUT
Open
Externally derived clock
Vcc
Vss
Note: Insert a damping resistor if required. The resistance will vary depending on the oscillator and the oscillation drive
capacity setting. Use the value recommended by the maker of the oscillator.
When the oscillation drive capacity is set to low, check that oscillation is stable.
Figure 5-1. Examples of main clock
Microcomputer
(Built-in feedback resistor)
XCIN
XCOUT
(Note)
RCd
CCIN
CCOUT
Microcomputer
(Built-in feedback resistor)
XCIN
XCOUT
Open
Externally derived clock
Vcc
Vss
Note: Insert a damping resistor if required. The resistance will vary depending on the oscillator and the oscillation drive
capacity setting. Use the value recommended by the maker of the oscillator.
When the oscillation drive capacity is set to low, check that oscillation is stable.
Figure 5-2. Examples of sub clock
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