EEPROM Library
EEPROM data memory is available with a number of dsPIC30 family and some PIC24 family MCU's. The mikroPascal PRO for dsPIC30/33 and PIC24 includes a library for comfortable work with MCU's internal EEPROM.
Library Routines
EEPROM_Erase
Prototype |
procedure EEPROM_Erase(address : longint); |
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Description |
Erases a single (16-bit) location from EEPROM memory. |
Parameters |
|
Returns |
Nothing. |
Requires |
Nothing. |
Example |
var eeAddr : longint; ... eeAddr := 0x7FFC80; EEPROM_Erase(eeAddr); |
Notes |
CPU is not halted for the Data Erase cycle. The user can poll WR bit, use NVMIF or Timer IRQ to detect the end of erase sequence. |
EEPROM_Erase_Block
Prototype |
procedure EEPROM_Erase_Block(address : longint); |
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Description |
Erases one EEPROM row from EEPROM memory; For dsPIC30 family it is 16 words long, for 24F04KA201 and 24F16KA102 family it is 8 words long. |
Parameters |
|
Returns |
Nothing. |
Requires |
Nothing. |
Example |
var eeAddr : longint; ... eeAddr := 0x7FFC20; EEPROM_Erase_Block(eeAddr); |
Notes |
CPU is not halted for the Data Erase cycle. The user can poll WR bit, use NVMIF or Timer IRQ to detect the end of erase sequence. |
EEPROM_Read
Prototype |
function EEPROM_Read(address : longint) : word; |
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Description |
Reads data from specified |
Parameters |
|
Returns |
Word from the specified address. |
Requires |
It is the user’s responsibility to obtain proper address parity (in this case, even). |
Example |
var eeAddr : longint; temp : word; ... eeAddr := 0x7FFC20; temp := EEPROM_Read(eeAddr); |
Notes |
None. |
EEPROM_Write
Prototype |
procedure EEPROM_Write(address : longint; data_ : word); |
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Description |
Writes |
Parameters |
|
Returns |
Nothing. |
Requires |
Nothing. |
Example |
var wrAddr : longint; eeData : word; ... eeData := 0xAAAA; wrAddr := 0x7FFC30; EEPROM_Write(wrAddr, eeData); |
Notes |
Specified memory location will be erased before writing starts. |
EEPROM_Write_Block
Prototype |
procedure EEPROM_Write_Block(address : longint; var data_ : array[100] of word); |
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Description |
Writes one EEPROM row (16 words block) of data. |
Parameters |
|
Returns |
Nothing. |
Requires |
It is the user's responsibility to maintain proper address alignment. In this case, address has to be a multiply of 32, which is the size (in bytes) of one row of MCU's EEPROM memory. |
Example |
var wrAddr : longint; data : string[16]; ... wrAddr := 0x7FFC20; data := 'mikroElektronika'; EEPROM_Write_Block(wrAddr, data); |
Notes |
|
Library Example
This project demonstrates usage of EEPROM library functions for dsPIC30F4013. Each EEPROM (16-bit) location can be written to individually, or in 16-word blocks, which is somewhat faster than the former. If Writing in blocks, EEPROM data start address must be a multiply of 16. Please read Help for more details on the library functions!
program Eeprom; var eeData, i : word; eeAddr : dword; dArr : array [16] of word; begin ADPCFG := 0xFFFF; // Disable analog inputs TRISB := 0; // PORTB as output LATB := 0xFFFF; eeAddr := 0x7FFC00; // Start address of EEPROM eeData := 0; // Data to be written while (eeData <= 0x00FF) do begin Eeprom_Write(eeAddr, eeData); // Write data into EEPROM Inc(eeData); while (WR_bit) do // Wait for write to finish, ; LATB := Eeprom_Read(eeAddr); // then, read the just-written data. eeAddr := eeAddr + 2; // Next address of EEPROM memory location Delay_ms(100); end; Delay_ms(1000); // Wait 1 second. eeData := 0xAAAA; for i := 0 to 15 do // Initializing array of 16 integers with data begin dArr[i] := eeData; eeData := not eeData; end; Eeprom_Write_Block(0x7FFC20, dArr); // Write entire row of EEPROM data while(WR_bit) do // Wait for write to finish ; eeAddr := 0x7FFC20; // Address of EEPROM where reading should start for i := 0 to 15 do // Read the data back begin LATB := Eeprom_Read(eeAddr); // and show it on PORTB eeAddr := eeAddr + 2; // Next address of EEPROM memory location Delay_ms(500); end end.
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