Data stored in nvsram failed in poweroff condition

[Anonymous]

Hi,

I am currently working on CY14C101J1 nvSRAM ,interfaced to atmega2560. I am facing issue related to retrieve the  data from nvsram after power off and on condition.

case: 1

int main()

{

    int8_t str[4] = {0xFF,0xBB,0xCC,0x55};

    int8_t rx_buffer[20];

    int8_t rx_buff[1];

   for(i=0;i<4;i++)

   {

         str = 0;

   }

    EEPROM_Memory_Write(&str,4,SLAVE_WRITE_ADDR1,0x1234);

    EEPROM_Commnd_Write(SLAVE_WRITE_ADDR1 , COMMND_REG, ASENB );

    EEPROM_Commnd_Write(SLAVE_WRITE_ADDR1 , COMMND_REG, STORE);

    EEPROM_Memory_Read(SLAVE_READ_ADDR1,SLAVE_WRITE_ADDR1,&rx_buffer,4,0x1234);

    _delay_ms(8000);

}

here, i am able to read the data in rx_buffer as 0xFF,0xBB,0xCC,0x55 before power off condition.

case: 2 But when i make the power off the board and power on ,i am not able to retrieve the same data in memory location (0x1234) .It showing some junk data . i tried the below steps to read the data.

    EEPROM_Commnd_Write(SLAVE_WRITE_ADDR1 , COMMND_REG, RECALL);

    _delay_ms(8000);

    EEPROM_Memory_Read(SLAVE_READ_ADDR1,SLAVE_WRITE_ADDR1,&rx_buffer,4,0x1234);

please help me to find the solution to read actual data after making  power off and on condition.For your reference,find below attached files.

*provide some pseudo code or steps to achieve?

Reply as soon as possible.

Thanks,

Arjun

[PradiptaB_11 · Accepted solution]

Hi,

We checked the schematics and found a external connection between VCC and the capacitor connected to the Vcap pin. Externally no connection was required. On removing the connection, the board is now working properly.

Thanks,

Pradipta.