Use EEPROM Memory

This example illustrates write and read from built-in EEPROM memory. The program works as follows. The main loop first reads EEPROM memory location at address 5. The program then enters an endless loop in which PORTB is incremented and the state of PORTA.2 input is checked. At the moment of pressing the push button marked MEMO, a number stored in PORTB will be saved in EEPROM at address 5 and directly read from it and shown on PORTD in binary format.

'Header******************************************************
program example_8 ' Program name
main: ' Start of program
ANSEL = 0 ' All I/O pins are configured as digital
ANSELH = 0
PORTB = 0 ' PORTB initial value
TRISB = 0 ' All PORTB pins are configured as outputs
PORTD = 0 ' PORTB initial value
TRISD = 0 ' All PORTD pins are configured as outputs
TRISA = 0xFF ' All PORTA pins are configured as inputs
PORTD = EEPROM_Read(5) ' Read EEPROM memory at address 5

while 1 ' Endless loop
 PORTB = PORTB + 1 ' Increment PORTB by 1
 Delay_ms(100) ' 100mS delay
 while not PORTA.B2 ' Remain in this loop as long as the button is pressed
 if not PORTA.B2 then
 EEPROM_Write(5,PORTB) ' If MEMO is pressed, save PORTB
 PORTD = EEPROM_Read(5) ' Read written data
 end if
 wend
wend

end. ' End of program

In order to make this example work properly, it is necessary to check the EEPROM library in the Library Manager prior to compiling:

• EEPROM

In order to check whether this program works properly, it is sufficient to press the MEMO push button and then turn off the microcontroller. After restarting it, the program will display on PORTD the value stored in EEPROM memory at addrsess 5. Remember that at the moment of writing, this value was displayed on PORTB.