GMS81004 Datasheet, PDF (89/101 Pages) Hynix Semiconductor – 8-BIT SINGLE CHIP MICROCOMPUTERS

* SRAM BACK-UP after Low Voltage Detection.
Chapter7. Reset Function
3.0V
about hours depend on Vcc-Gnd Capacitor
MCU OPR.
Voltage
1.8V(TYP)
( 20¡É)
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
* 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
7 -5