
Rev. 1.10
38
March 02, 2020
Rev. 1.10
39
March 02, 2020
BS83A02L/BS83B04L
Ultra-Low Power Touch Key Flash MCU
BS83A02L/BS83B04L
Ultra-Low Power Touch Key Flash MCU
IDLE1 Mode
The IDLE1 Mode is entered when a HALT instruction is executed and when the FHIDEN bit in the
SCC register is high and the FSIDEN bit in the SCC register is high. In the IDLE1 Mode the CPU
will be switched off but both the high and low speed oscillators will be turned on to provide a clock
source to keep some peripheral functions operational.
IDLE2 Mode
The IDLE2 Mode is entered when a HALT instruction is executed and when the FHIDEN bit in the
SCC register is high and the FSIDEN bit in the SCC register is low. In the IDLE2 Mode the CPU
will be switched off but the high speed oscillator will be turned on to provide a clock source to keep
some peripheral functions operational.
Control Registers
The registers, SCC and HIRCC, are used to control the internal clocks within the devices.
Register
Name
Bit
7
6
5
4
3
2
1
0
SCC
CKS2
CKS1
CKS0
—
—
—
FHIDEN FSIDEN
HIRCC
(BS83A02L)
—
—
—
—
—
—
HIRCF
HIRCEN
HIRCC
(BS83B04L)
—
—
—
—
HIRC1
HIRC0
HIRCF
HIRCEN
System Operating Mode Control Register List
• SCC Register
Bit
7
6
5
4
3
2
1
0
Name
CKS2
CKS1
CKS0
—
—
—
FHIDEN FSIDEN
R/W
R/W
R/W
R/W
—
—
—
R/W
R/W
POR
0
0
0
—
—
—
0
0
Bit 7~5
CKS2~CKS0
: System clock selection
000: f
H
001: f
H
/2
010: f
H
/4
011: f
H
/8
100: f
H
/16
101: f
H
/32
110: f
H
/64
111: f
SUB
These three bits are used to select which clock is used as the system clock source. In
addition to the system clock source directly derived from f
H
or f
SUB
, a divided version
of the high speed system oscillator can also be chosen as the system clock source.
Bit 4~2
Unimplemented, read as “0”
Bit 1
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 a “HALT” instruction.
Bit 0
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 a “HALT” instruction.