GMS81C50 Datasheet, PDF (81/99 Pages) Hynix Semiconductor – 8-BIT SINGLE CHIP MICROCONTROLLERS

GMS81C50 Series
HYUNDAI
3.0V
about hours depend on Vcc-Gnd Capacitor
MCU OPR.
Voltage
1.8V(TYP)
( 20
(
0.7V(VRET)
0V
Low Voltage Detection
point
Power On Reset
( SRAM retention)
* SRAM Data Backup
Power On Reset
( SRAM unstable )
User
Removes
Batteries
* The operation after Low voltage detection
Interrupt : disable
Stop release : disable
All I/O port : input Mode
Remout port : Low Level
OSC
: STOP
All I/O port pull-up ON (Mask Option )
SRAM Data retention
User
Replace
Batteries
Figure 16-6 Low Voltage Detection and Protection
(5) S/W flow chart example after Reset using SRAM Back-up
RESET
Stack Pointer initialize
Check the SRAM value
(RAM Pattern, Check sum..)
SRAM DATA IS VALID? ^N
Y
Use saved SRAM
value
Clear All Ram area
Figure 16-7 S/W Flow Chart Example for SRAM Back-up
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