memory.c

/*
    (c) 2016 Microchip Technology Inc. and its subsidiaries. You may use this
    software and any derivatives exclusively with Microchip products.

    THIS SOFTWARE IS SUPPLIED BY MICROCHIP "AS IS". NO WARRANTIES, WHETHER
    EXPRESS, IMPLIED OR STATUTORY, APPLY TO THIS SOFTWARE, INCLUDING ANY IMPLIED
    WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY, AND FITNESS FOR A
    PARTICULAR PURPOSE, OR ITS INTERACTION WITH MICROCHIP PRODUCTS, COMBINATION
    WITH ANY OTHER PRODUCTS, OR USE IN ANY APPLICATION.

    IN NO EVENT WILL MICROCHIP BE LIABLE FOR ANY INDIRECT, SPECIAL, PUNITIVE,
    INCIDENTAL OR CONSEQUENTIAL LOSS, DAMAGE, COST OR EXPENSE OF ANY KIND
    WHATSOEVER RELATED TO THE SOFTWARE, HOWEVER CAUSED, EVEN IF MICROCHIP HAS
    BEEN ADVISED OF THE POSSIBILITY OR THE DAMAGES ARE FORESEEABLE. TO THE
    FULLEST EXTENT ALLOWED BY LAW, MICROCHIP'S TOTAL LIABILITY ON ALL CLAIMS IN
    ANY WAY RELATED TO THIS SOFTWARE WILL NOT EXCEED THE AMOUNT OF FEES, IF ANY,
    THAT YOU HAVE PAID DIRECTLY TO MICROCHIP FOR THIS SOFTWARE.

    MICROCHIP PROVIDES THIS SOFTWARE CONDITIONALLY UPON YOUR ACCEPTANCE OF THESE
    TERMS.
*/

/**
  Section: Included Files
*/
#include <xc.h>
#include "memory.h"


/**
  Section: Flash Module APIs
*/

uint16_t FLASH_ReadWord(uint16_t flashAddr) {
    PMADRL = (flashAddr & 0x00FF);
    PMADRH = ((flashAddr & 0xFF00) >> 8);

    PMCON1bits.CFGS = 0;// Deselect Configuration space
    PMCON1bits.RD = 1;  // Initiate Read
    NOP();
    NOP();

    return ((uint16_t) ((PMDATH << 8) | PMDATL));
}

int8_t FLASH_WriteBlock(uint16_t writeAddr, uint16_t *flashWordArray) {
    uint16_t blockStartAddr = (uint16_t) (writeAddr & ((END_FLASH - 1) ^ (ERASE_FLASH_BLOCKSIZE - 1)));
    uint8_t i;

    // Flash write must start at the beginning of a row
    if (writeAddr != blockStartAddr) {
        return -1;
    }

    // Block write sequence
    PMCON1bits.WREN = 1;// Enable wrties
    PMCON1bits.CFGS = 0;// Deselect Configuration space
    PMCON1bits.LWLO = 1;// Only load write latches

    for (i = 0; i < WRITE_FLASH_BLOCKSIZE; i++) {
        // Load lower 8 bits of write address
        PMADRL = (writeAddr & 0xFF);
        // Load upper 6 bits of write address
        PMADRH = ((writeAddr & 0x0F00) >> 8);

        if (i == (WRITE_FLASH_BLOCKSIZE - 1)) {
            // Start Flash program memory write
            PMCON1bits.LWLO = 0;
        }

        // Load data in current address
        PMDATL = (uint8_t) flashWordArray[i];
        PMDATH = (uint8_t) ((flashWordArray[i] & 0xFF00) >> 8);


        PMCON2 = 0x55;
        PMCON2 = 0xAA;
        PMCON1bits.WR = 1;
        NOP();
        NOP();

        writeAddr++;
    }

    PMCON1bits.WREN = 0;// Disable writes

    return 0;
}

void FLASH_EraseBlock(uint16_t startAddr) {
    // Load lower 8 bits of erase address boundary
    PMADRL = (startAddr & 0xFF);
    // Load upper 6 bits of erase address boundary
    PMADRH = ((startAddr & 0xFF00) >> 8);

    // Block erase sequence
    PMCON1bits.CFGS = 0;// Deselect Configuration space
    PMCON1bits.FREE = 1;// Specify an erase operation
    PMCON1bits.WREN = 1;// Allows erase cycles

    // Start of required sequence to initiate erase
    PMCON2 = 0x55;
    PMCON2 = 0xAA;
    PMCON1bits.WR = 1;// Set WR bit to begin erase
    NOP();
    NOP();

    PMCON1bits.WREN = 0;// Disable writes
}
/**
 End of File
*/