typedef struct wiz_NetInfo_t
{
   uint8_t mac[6];  ///< Source Mac Address
   uint8_t ip[4];   ///< Source IP Address
   uint8_t sn[4];   ///< Subnet Mask
   uint8_t gw[4];   ///< Gateway IP Address
}wiz_NetInfo;

//==================================================================================================
typedef struct N_flash_GlobalSettingAllVar{
    uint32_t ID;
    //----------------------------------------------
	wiz_NetInfo WiznetSetting;
    //----------------------------------------------
	S_IpAdrAccess IpAdrAccess[4];
    uint8_t NumberActiveIP;
    ....................
}


Обявляем в секции default(определенный адрес) структру и сразу заполняем дефолтными значеним

const S_flash_GlobalSettingAllVar Flash_default_Settings@".default"={
    .ID=0xAABBCCDD,
#ifdef BORD_AVTO_RELEASE
	.WiznetSetting={
		.mac = {0x02, 0x01, 0x01, 0x01, 0x01, 0x01},	//6
		.ip = {192, 168, 0, 117},						//4
		.sn = {255, 255, 255,0},
		.gw = {192, 168, 0, 1},
	},
#else
	.WiznetSetting={
		.mac = {0x02, 0x01, 0x01, 0x01, 0x01, 0x01},	//6
		.ip = {192, 168, 0, 117},						//4
		.sn = {255, 255, 255,0},
		.gw = {192, 168, 0, 1},
	},
	....................
}



использутется это так

Типа парсинг JSON

ConvStrToip(RAM_SettingAllVar.WiznetSetting.ip,(uint8_t*)TempVarValue[JsonGetValue("Ip_adress")]);		//IP
ConvStrToip(RAM_SettingAllVar.WiznetSetting.sn,(uint8_t*)TempVarValue[JsonGetValue("Subnet_Mask")]);	//Mask
ConvStrToip(RAM_SettingAllVar.WiznetSetting.gw,(uint8_t*)TempVarValue[JsonGetValue("gateway")]);		//Gateway
ConvStrToMac(RAM_SettingAllVar.WiznetSetting.mac,(uint8_t*)TempVarValue[JsonGetValue("MacAddr")]);		//IP

Write_SettingVAR_flash();  // записать изменения

//==================================================================================================
/*
	* @Описание:	1) Стереть всю таблицу
					2) записать всю структуру
	* @Параметр:
	* @Возврат:		Нету
*/
void Write_SettingVAR_flash(void){
	//-----------------------------------------------------------------------------------------------------
	FLASH_ErasePage((uint32_t)&Flash_Start_Settings);
	FLASH_ProgramPage((uint32_t)&Flash_Start_Settings,(unsigned char*)&RAM_SettingAllVar,Table_flash_Setting_len);
	//-----------------------------------------------------------------------------------------------------
}