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Workaround B: Low Battery Detection Using Wake-Up Timer

//**Function PROTOTYPES**

//MCU initialization

void MCU_Init(void);

//SPI functions

void SpiWriteRegister (U8, U8);

U8 SpiReadRegister (U8);

//GLOBAL VARIABLE

xdata U16 wWaitCnt;

void main(void)

{

U8 ItStatus1,ItStatus2,Battery_Voltage_Level,LBDT;

U16 delay;

U8 temp8;

//Initialize the MCU:

//

- set IO ports for the Software Development board

//

- set MCU clock source

//

- initialize the SPI port

//

- turn off LEDs

MCU_Init();

//

Initialize the Si4x3x ISM chip

//read interrupt status registers to clear the interrupt flags and release NIRQ pin

ItStatus1 = SpiReadRegister(0x03);

//read the Interrupt Status1 register

ItStatus2 = SpiReadRegister(0x04);

//read the Interrupt Status2 register

for (temp8=0;temp8<15;temp8++)

{

for(delay=0;delay<10000;delay++);