m37905 Renesas Electronics Corporation., m37905 Datasheet - Page 69

• Manufacturer Part Number: m37905
• Description: Mitsubishi 16-bit Single-chip Microcomputer 7700 Family / 7900 Series
• Manufacturer: Renesas Electronics Corporation.

CLOCK GENERATING CIRCUIT
4.2 Clocks
Fig. 4.2.3 Setting procedure for clock control register 0 when using PLL frequency multiplier
4-8
Setting of system clock select bit to “1.”
Notes 1: After reset, these bits are allowed to be changed only once. If
b7
b7
2: This decision is unnecessary If double is selected and the
0 0
1 1
it is necessary to write a certain value to these bits, be sure to
write the same value that has been written after the latest reset.
period of RESET = “L” is “the oscillation stabilizing time of an
oscillator + 2 ms” or more.
7905 Group User’s Manual Rev.1.0
1
1
2 ms elapsed ?
b0
1
b3 b2
b0
System clock select bit
PLL frequency multiplier is active, and pin
V
PLL multiplication ratio select bits (Note 1)
0 1 :
1 0 :
1 1 :
1
Clock control register 0 (Address BC
CONT
0 : fX
System clock select bit
Clock control register 0 (Address BC
0 : f
Y
is valid.
IN
2
3
4
PLL
N
(Note 2)
16
)
16
)