Toshiba TLCS-900/H1 Series Manual page 38

3.4.5 Noise reduction circuits
Noise reduction circuits are built in, allowing implementation of the following features.
(1) Reduced drivability for high-frequency oscillator circuit
(2) Reduced drivability for low-frequency oscillator circuit
(3) Single drive for high-frequency oscillator circuit
(4) Runaway prevention using SFR protection register
These are set in EMCCR0 to EMCCR2 registers.
(1) Reduced drivability for high-frequency oscillator circuit
(Purpose)
Reduces noise and power for oscillator when a resonator is used.
(Clock diagram)
Resonator
(Setting method)
The drivability of the oscillator is reduced by writing"0" to EMCCR0<DRVOSCH>
register. At reset, <DRVOSCH> is initialized to "1" and the oscillator starts oscillation
by normal-drivability when the power-supply is on.
Note: This function (EMCCR0<DRVODCH>= "0") is available when f
X1 pin
C1
C2
X2 pin
92CF30-36
f
OSCH
Enable oscillation
EMCCR0<DRVOSCH>
= 6 to 10MHz.
OSCH
TMP92CF30
2009-06-12