HT66F4360 Datasheet, PDF (68/263 Pages) Holtek Semiconductor Inc – Smart Card Reader Flash MCU

HT66F4360/HT66F4370/HT66F4390
Smart Card Reader Flash MCU
Bit 2
Bit 1
Bit 0
FSS: Low Frequency clock selection
0: LIRC
1: LXT
FHIDEN: High Frequency oscillator control when CPU is switched off
0: Disable
1: Enable
This bit is used to control whether the high speed oscillator is activated or stopped
when the CPU is switched off by executing an “HALT” instruction.
FSIDEN: Low Frequency oscillator control when CPU is switched off
0: Disable
1: Enable
This bit is used to control whether the low speed oscillator is activated or stopped
when the CPU is switched off by executing an “HALT” instruction. The low frequency
oscillator is controlled by this bit together with the WDT function enable control. If
this bit is cleared to 0 but the WDT function is enabled, the fWDT clock will also be
enabled.
HIRCC Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
HIRCF HIRCEN
R/W
—
—
—
—
—
—
R
R/W
POR
—
—
—
—
—
—
0
1
Bit 7~2
Bit 1
Bit 0
Unimplemented, read as “0”
HIRCF: HIRC oscillator stable flag
0: HIRC unstable
1: HIRC stable
This bit is used to indicate whether the HIRC oscillator is stable or not. When the
HIRCEN bit is set to 1 to enable the HIRC oscillator, the HIRCF bit will first be
cleared to 0 and then set to 1 after the HIRC oscillator is stable.
HIRCEN: HIRC oscillator enable control
0: Disable
1: Enable
Rev. 1.30
68
December 15, 2016