System Operation Modes - Holtek BS83A04C Manual

BS83A04C
4-Key Enhanced Touch I/O Flash MCU
High Speed
Oscillator
HIRCEN HIRC
Low Speed
Oscillator
LIRC
Note: When the system clock source f
stopped to conserve the power or continue to oscillate to provide the clock source, f
for peripheral circuit to use, which is determined by configuring 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 specific performance and
power requirements of the application. There are two modes allowing normal operation of the
microcontroller, the FAST 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
CPU
Mode
FAST On
SLOW On
IDLE0 Off
IDLE1 Off
IDLE2 Off
SLEEP Off
Note: 1. The f clock will be switched on or off by configuring the corresponding oscillator enable
H
bit in the SLOW mode.
2. The f
LIRC
mode.
Rev. 1.00
IDLE0
SLEEP
IDLE2
SLEEP
f
LIRC
WDT
Device Clock Configurations
is switched to f
SYS
Register Setting
FHIDEN FSIDEN CKS2~CKS0
x x
x x
0 1
1 1
1 0
0 0
clock will be switched on since the WDT function is always enabled in the SLEEP
33
f
H
f
H
f
H
Prescaler
f /16
H
f /32
H
f /64
H
f
SUB
f
SUB
f
f /4
PSC
SYS
Prescaler
f
SYS
CLKSEL[1:0]
from f , the high speed oscillator can be
SUB H
f f
SYS H
000~110 f ~f /64 On
H H
111 f On/Off
SUB
000~110 Off
Off
111 On
xxx On On
000~110 On
On
111 Off
xxx Off Off
f
H
/2
/4
/8
f
SYS
CKS2~CKS0
f
SUB
TBON
Time
Base
TB[2:0]
~f /64,
H H
f f
SUB LIRC
On On
(1)
On On
On On
On On
Off On
(2)
Off On
"x": Don't care
March 24, 2020