mirror of
https://github.com/raphnet/gc_n64_usb-v3
synced 2024-11-10 19:25:07 -05:00
73 lines
2.0 KiB
C
73 lines
2.0 KiB
C
/* wusbmote: Wiimote accessory to USB Adapter
|
|
* Copyright (C) 2012-2014 Raphaël Assénat
|
|
*
|
|
* 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, write to the Free Software Foundation, Inc.,
|
|
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
|
|
*
|
|
* The author may be contacted at raph@raphnet.net
|
|
*/
|
|
|
|
#include <avr/eeprom.h>
|
|
#include <util/crc16.h>
|
|
#include <stdint.h>
|
|
#include <string.h>
|
|
#include "eeprom.h"
|
|
|
|
static uint16_t calc_geeprom_data_crc(void)
|
|
{
|
|
uint16_t crc = 0x0000;
|
|
int i;
|
|
|
|
/* Update the CRC */
|
|
for (i=0; i<EEPROM_USED_SIZE_NOCRC; i++) {
|
|
crc = _crc_xmodem_update(crc, ((uint8_t*)&g_eeprom_data)[i]);
|
|
}
|
|
|
|
return crc;
|
|
}
|
|
|
|
void eeprom_commit(void)
|
|
{
|
|
g_eeprom_data.crc16 = calc_geeprom_data_crc();
|
|
|
|
/* Sync eeprom content */
|
|
eeprom_update_block(&g_eeprom_data, EEPROM_BASE_PTR, EEPROM_USED_SIZE);
|
|
}
|
|
|
|
static char isCrcValid()
|
|
{
|
|
return g_eeprom_data.crc16 == calc_geeprom_data_crc();
|
|
}
|
|
|
|
// return 1 if eeprom was blank
|
|
void eeprom_init(void)
|
|
{
|
|
eeprom_read_block(&g_eeprom_data, EEPROM_BASE_PTR, EEPROM_USED_SIZE);
|
|
|
|
/* Detect new or corrupted content. Program default values if required. */
|
|
if ((g_eeprom_data.magic != EEPROM_MAGIC) || !isCrcValid())
|
|
{
|
|
memset(&g_eeprom_data, 0, EEPROM_USED_SIZE);
|
|
g_eeprom_data.magic = EEPROM_MAGIC;
|
|
|
|
// Call application code to set application defaults
|
|
eeprom_app_write_defaults();
|
|
|
|
// Write the now valid content to the EEPROM at once.
|
|
eeprom_commit();
|
|
}
|
|
|
|
eeprom_app_ready();
|
|
}
|