text: /* Copyright 2017 Fred Sundvik
   *
   * This program is free software: you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation, either version 2 of the License, or
   * (at your option) any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program.  If not, see <http://www.gnu.org/licenses/>.
   */
  
  #include "eeprom.h"
  
  #define EEPROM_SIZE 32
  
  static uint8_t buffer[EEPROM_SIZE];
  
  uint8_t eeprom_read_byte(const uint8_t *addr) {
      uintptr_t offset = (uintptr_t)addr;
      return buffer[offset];
  }
  
  void eeprom_write_byte(uint8_t *addr, uint8_t value) {
      uintptr_t offset = (uintptr_t)addr;
      buffer[offset]   = value;
  }
  
  uint16_t eeprom_read_word(const uint16_t *addr) {
      const uint8_t *p = (const uint8_t *)addr;
      return eeprom_read_byte(p) | (eeprom_read_byte(p + 1) << 8);
  }
  
  uint32_t eeprom_read_dword(const uint32_t *addr) {
      const uint8_t *p = (const uint8_t *)addr;
      return eeprom_read_byte(p) | (eeprom_read_byte(p + 1) << 8) | (eeprom_read_byte(p + 2) << 16) | (eeprom_read_byte(p + 3) << 24);
  }
  
  void eeprom_read_block(void *buf, const void *addr, uint32_t len) {
      const uint8_t *p    = (const uint8_t *)addr;
      uint8_t *      dest = (uint8_t *)buf;
      while (len--) {
          *dest++ = eeprom_read_byte(p++);
      }
  }
  
  void eeprom_write_word(uint16_t *addr, uint16_t value) {
      uint8_t *p = (uint8_t *)addr;
      eeprom_write_byte(p++, value);
      eeprom_write_byte(p, value >> 8);
  }
  
  void eeprom_write_dword(uint32_t *addr, uint32_t value) {
      uint8_t *p = (uint8_t *)addr;
      eeprom_write_byte(p++, value);
      eeprom_write_byte(p++, value >> 8);
      eeprom_write_byte(p++, value >> 16);
      eeprom_write_byte(p, value >> 24);
  }
  
  void eeprom_write_block(const void *buf, void *addr, uint32_t len) {
      uint8_t *      p   = (uint8_t *)addr;
      const uint8_t *src = (const uint8_t *)buf;
      while (len--) {
          eeprom_write_byte(p++, *src++);
      }
  }
  
  void eeprom_update_byte(uint8_t *addr, uint8_t value) { eeprom_write_byte(addr, value); }
  
  void eeprom_update_word(uint16_t *addr, uint16_t value) {
      uint8_t *p = (uint8_t *)addr;
      eeprom_write_byte(p++, value);
      eeprom_write_byte(p, value >> 8);
  }
  
  void eeprom_update_dword(uint32_t *addr, uint32_t value) {
      uint8_t *p = (uint8_t *)addr;
      eeprom_write_byte(p++, value);
      eeprom_write_byte(p++, value >> 8);
      eeprom_write_byte(p++, value >> 16);
      eeprom_write_byte(p, value >> 24);
  }
  
  void eeprom_update_block(const void *buf, void *addr, uint32_t len) {
      uint8_t *      p   = (uint8_t *)addr;
      const uint8_t *src = (const uint8_t *)buf;
      while (len--) {
          eeprom_write_byte(p++, *src++);
      }
  }
  