Holtek BS83A04C Manual page 37

BS83A04C
4-Key Enhanced Touch I/O Flash MCU
SLOW Mode to FAST Mode Switching
In SLOW mode the system clock is derived from f
FAST mode from f
clock will respectively be switched to f
However, if f is not used in SLOW mode and thus switched off, it will take some time to re-
H
oscillate and stabilise when switching to the FAST mode from the SLOW Mode. This is monitored
using the HIRCF bit in the HIRCC register. The time duration required for the high speed system
oscillator stabilization is specified in the System Start Up Time Characteristics.
Rev. 1.00
FHIDEN=0, FSIDEN=0
HALT instruction is executed
FHIDEN=0, FSIDEN=1
HALT instruction is executed
IDLE0 Mode
FHIDEN=1, FSIDEN=1
HALT instruction is executed
IDLE1 Mode
FHIDEN=1, FSIDEN=0
HALT instruction is executed
IDLE2 Mode
, the CKS2~CKS0 bits should be set to "000"~"110" and then the system
SUB
~f /64.
H H
FHIDEN=0, FSIDEN=0
HALT instruction is executed
FHIDEN=0, FSIDEN=1
HALT instruction is executed
IDLE0 Mode
FHIDEN=1, FSIDEN=1
HALT instruction is executed
IDLE1 Mode
FHIDEN=1, FSIDEN=0
HALT instruction is executed
IDLE2 Mode
37
FAST Mode
CKS2~CKS0=111
SLOW Mode
SLEEP Mode
. When system clock is switched back to the
SUB
SLOW Mode
CKS2~CKS0=000~110
FAST Mode
SLEEP Mode
March 24, 2020