Holtek BS66F340 - System Operation Modes

Rev. 1.60 70 August 20, 2019 Rev. 1.60 71 August 20, 2019
BS66F340/BS66F350/BS66F360/BS66F370
Touch A/D Flash MCU with LED Driver
BS66F340/BS66F350/BS66F360/BS66F370
Touch A/D Flash MCU with LED Driver
HXT
Prescaler
f
H
LXT
High Speed
Oscillators
Low Speed
Oscillators
f
H
/2
f
H
/16
f
H
/64
f
H
/8
f
H
/4
f
H
/32
CKS2~CKS0
f
SYS
f
SUB
f
SUB
HXTEN
FSS
LIRC
LXTEN
f
LIRC
f
LIRC
HIRC
HIRCEN
f
H
LVR
WDT
f
LIRC
f
SYS
/4
f
PSC0
Time Base 0
CLKSEL0[1:0]
f
SUB
f
SYS
Prescaler 0
TB0[2:0]
f
SYS
/4
CLKSEL1[1:0]
f
SUB
f
SYS
FHS
f
PSC1
Time Base 1Prescaler 1
TB1[2:0]
Device Clock Congurations
Note: When the system clock source f
SYS
is switched to f
SUB
from f
H
, the high speed oscillation
can be stopped to conserve the power or continue to oscillate to provide the clock source,
f
H
~f
H
/64, for peripheral circuit to use, which is determined by conguring the corresponding
high speed oscillator enable control bit.
System Operation Modes
There are six different modes of operation for the microcontroller, each one with its own special
characteristics and which can be chosen according to the specic performance and power requirements
of the application. There are two modes allowing normal operation of the microcontroller, the
NORMAL Mode and SLOW Mode. The remaining four modes, the SLEEP, IDLE0, IDLE1 and
IDLE2 Mode are used when the microcontroller CPU is switched off to conserve power.
Operation
Mode
CPU
Register Setting
f
SYS
f
H
f
SUB
f
LIRC
FHIDEN FSIDEN CKS2~CKS0
NORMAL On x x 000~110 f
H
~f
H
/64 On On On
SLOW On x x 111 f
SUB
On/Off
(1)
On On
IDLE0 Off 0 1
000~110 Off
Off On On
111 On
IDLE1 Off 1 1 xxx On On On On
IDLE2 Off 1 0
000~110 On
On Off On
111 Off
SLEEP Off 0 0 xxx Off Off Off On
(2)
Note: 1. The f
H
clock will be switched on or off by conguring the corresponding oscillator enable bit
in the SLOW mode.
2. The f
LIRC
clock will be switched on since the WDT function is always enabled.