void tx_timed_sleep_GPIO_INIT(){        RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB,ENABLE);        GPIO_InitTypeDef GPIO_Init_structure;        GPIO_Init_structure.GPIO_Mode=GPIO_Mode_IPU;        GPIO_Init_structure.GPIO_Pin=GPIO_Pin_8;        GPIO_Init_structure.GPIO_Speed=GPIO_Speed_50MHz;        GPIO_Init(GPIOB,&GPIO_Init_structure);}/*** Application entry point.*/int tx_timed_sleep(void){    uint16_t lp_osc_freq, sleep_cnt;                tx_timed_sleep_GPIO_INIT();    /* 串口输出应用名称. Display application name on LCD. */    _dbg_printf((unsigned char *)APP_NAME);    /* 配置SPI快速率. Configure SPI rate, DW3000 supports up to 38 MHz */    port_set_dw_ic_spi_fastrate();    /* 硬复位DW3000模块. Reset DW IC */    reset_DWIC(); /* Target specific drive of RSTn line into DW IC low for a period. */    Sleep(2); // Time needed for DW3000 to start up (transition from INIT_RC to IDLE_RC)    /* 检查DW3000模块是否处于IDLE_RC */    while (!dwt_checkidlerc()) /* Need to make sure DW IC is in IDLE_RC before proceeding */    { };    /* 初始化DW3000模块 */    if (dwt_initialise(DWT_DW_INIT) == DWT_ERROR)    {        _dbg_printf((unsigned char *)"INIT FAILED     ");        while (1)        { };    }    /* 清除SPI就绪中断. Clearing the SPI ready interrupt*/    dwt_write32bitreg(SYS_STATUS_ID, SYS_STATUS_RCINIT_BIT_MASK | SYS_STATUS_SPIRDY_BIT_MASK);    /* 配置DW3000中断函数. Install DW IC IRQ handler. NOTE: the IRQ line must have a PULLDOWN or else it may trigger incorrectly when the device is sleeping*///    port_set_dwic_isr(dwt_isr);    /* 校准和配置UWB计数. Calibrate and configure sleep count. */    lp_osc_freq = XTAL_FREQ_HZ / dwt_calibratesleepcnt();    sleep_cnt = ((SLEEP_TIME_MS * ((uint32_t) lp_osc_freq)) / 1000) >> 12;    //sleep_cnt = 0x06; // 1 step is ~ 175ms, 6 ~= 1s    dwt_configuresleepcnt(sleep_cnt);    /* 配置DW3000信道参数. Configure DW IC. See NOTE 6 below. */    if(dwt_configure(&config)) /* if the dwt_configure returns DWT_ERROR either the PLL or RX calibration has failed the host should reset the device */    {        _dbg_printf((unsigned char *)"CONFIG FAILED     ");        while (1)        { };    }    /* 配置DW3000发送频谱参数. Configure the TX spectrum parameters (power, PG delay and PG count) */    dwt_configuretxrf(&txconfig_options);    /* 配置DW3000发送频谱参数. Configure sleep and wake-up parameters. */    dwt_configuresleep(DWT_CONFIG, DWT_PRES_SLEEP | DWT_WAKE_CSN | DWT_SLEEP | DWT_SLP_EN);    /* 注册中断回调函数. Register the call-backs (only SPI ready callback is used). */    dwt_setcallbacks(NULL, NULL, NULL, NULL, NULL, &spi_ready_cb);    port_EnableEXT_IRQ();    _dbg_printf("配置成功\n");    /* Loop forever sending frames periodically. */    while (1)    {        /* DW3000进入休眠模式,唤醒后进入IDLE. Put DW IC to sleep. Go to IDLE state after wakeup*/        dwt_entersleep(DWT_DW_IDLE);        sleeping = 1;        /* In this example, there is nothing to do to wake the DW IC up as it is handled by the sleep timer. */        while (sleeping)        {Sleep(1);}; /* Wait for device to wake up */        /* 增加延时.必要*/        Sleep(5);                                if(KEY==0)                                {        _dbg_printf((unsigned char *)"唤醒成功:%04x\n", dwt_readdevid());        /* 唤醒时恢复所有配置. Restore the required configurations on wake */        dwt_restoreconfig();        /* Increment the blink frame sequence number (modulo 256). */        tx_msg[BLINK_FRAME_SN_IDX]++;                                        /* 写入待发送数据到DW3000准备发送,并设置发送长度. Write frame data to DW IC and prepare transmission. See NOTE 4 below. */        dwt_writetxdata(sizeof(tx_msg), tx_msg, 0); /* Zero offset in TX buffer. */        dwt_writetxfctrl(sizeof(tx_msg), 0, 0); /* Zero offset in TX buffer, no ranging. */        /* 立即发送. Start transmission. */        dwt_starttx(DWT_START_TX_IMMEDIATE);        /* 查询DW3000是否发送成功. It is not possible to access DW IC registers once it has sent the frame and gone to sleep, and therefore we do not try to poll for TX         * frame sent, but instead simply wait sufficient time for the DW IC to wake up again before we loop back to send another frame.         * If interrupts are enabled, (e.g. if MTXFRS bit is set in the SYS_MASK register) then the TXFRS event will cause an active interrupt and         * prevent the DW IC from sleeping. */        /* Poll DW IC until TX frame sent event set. See NOTE 7 below.         * STATUS register is 4 bytes long but, as the event we are looking at is in the first byte of the register, we can use this simplest API         * function to access it.*/        while (!(dwt_read32bitreg(SYS_STATUS_ID) & SYS_STATUS_TXFRS_BIT_MASK))        {};        /* 清除发送完成事件. Clear TX frame sent event. */        dwt_write32bitreg(SYS_STATUS_ID, SYS_STATUS_TXFRS_BIT_MASK);                                }    }}