七夕鹊桥搭建-基于超宽带技术的心动“鹊桥”设计

AUST · 发表于 2019-8-7 20:43:29

本帖最后由 AUST 于 2019-8-8 21:19 编辑

“那一眼看见你，就知道这辈子都逃不掉了”。曾听过这样一句话：“从不想独身，却有预感晚婚，我想在茫茫人海中寻找那唯一与之契合的灵魂伴侣。”

因为今天，又到了牛郎织女见面的日子——七夕。

同样，今天也是2019年大学生电子设计竞赛开赛的日子，祝愿赛场上的你们都取得好成绩！

一、思路篇

本人和女友也是在异地中，常常以“两情若是久长时，又岂在朝朝暮暮。”来安慰自己。晚上无意看到这个征集帖，就想利用手上的UWB模块做一个“心动鹊桥”。主要功能：在有效范围内，两个模块距离越近，红色LED闪烁越快，寓意着心跳越快。当两个模块完全接近时，红色LED常亮，寓意着彼此惺惺相惜。

二、原理篇

双向飞行时间法（TW-TOF,two way-time of flight）每个模块从启动开始即会生成一条独立的时间戳。模块 A 的发射机在其时间戳上的 Ta1 发射请求性质的脉冲信号，模块 B 在 Tb2 时刻发射一个响应性质的信号，被模块 A 在自己的时间戳 Ta2 时刻接收。有次可以计算出脉冲信号在两个模块之间的飞行时间，从而确定飞行距离 S。

S=Cx[(Ta2-Ta1)-(Tb2-Tb1)]/2 (C 为光速)

二、软件篇

SPI初始化

/***************************************************************************************************
*函数名: Spi_Init
*功能说明: SPI从机设备CS引脚初始化
*形参: 无
*返回值: 无
***************************************************************************************************/
void SPI_Configuration(void)
{
SPI_InitTypeDef SPI_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
SPI_I2S_DeInit(SPIx);
GPIO_PinRemapConfig(GPIO_Remap_SWJ_JTAGDisable, ENABLE);
SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
SPI_InitStructure.SPI_Mode = SPI_Mode_Master;
SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;
SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;
SPI_InitStructure.SPI_CPHA = SPI_CPHA_1Edge;
SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;
SPI_InitStructure.SPI_BaudRatePrescaler = SPIx_PRESCALER;
SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
SPI_InitStructure.SPI_CRCPolynomial = 7;
SPI_Init(SPIx, &SPI_InitStructure);
// SPIx SCK and MOSI pin setup
GPIO_InitStructure.GPIO_Pin = SPIx_SCK | SPIx_MOSI;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(SPIx_GPIO, &GPIO_InitStructure);
// SPIx MISO pin setup
GPIO_InitStructure.GPIO_Pin = SPIx_MISO;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
GPIO_Init(SPIx_GPIO, &GPIO_InitStructure);
// SPIx CS pin setup
GPIO_InitStructure.GPIO_Pin = SPIx_CS;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(SPIx_CS_GPIO, &GPIO_InitStructure);
// Disable SPIx SS Output
SPI_SSOutputCmd(SPIx, DISABLE);
// Enable SPIx
SPI_Cmd(SPIx, ENABLE);
// Set CS high
GPIO_SetBits(SPIx_CS_GPIO, SPIx_CS);
}

复制代码

USART2初始化

/***************************************************************************************************
*函数名: uart_init
*功能说明: USART2初始化
*形参: bound波特率
*返回值: 无
***************************************************************************************************/
void uart_init(u32 bound){
GPIO_InitTypeDef gpioInitStruct;
USART_InitTypeDef usartInitStruct;
NVIC_InitTypeDef nvicInitStruct;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE);
//PA2 TXD
gpioInitStruct.GPIO_Mode = GPIO_Mode_AF_PP;
gpioInitStruct.GPIO_Pin = GPIO_Pin_2;
gpioInitStruct.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &gpioInitStruct);
//PA3 RXD
gpioInitStruct.GPIO_Mode = GPIO_Mode_IN_FLOATING;
gpioInitStruct.GPIO_Pin = GPIO_Pin_3;
gpioInitStruct.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &gpioInitStruct);
usartInitStruct.USART_BaudRate = bound;
usartInitStruct.USART_HardwareFlowControl = USART_HardwareFlowControl_None; //无硬件流控
usartInitStruct.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; //接收和发送
usartInitStruct.USART_Parity = USART_Parity_No; //无校验
usartInitStruct.USART_StopBits = USART_StopBits_1; //1位停止位
usartInitStruct.USART_WordLength = USART_WordLength_8b; //8位数据位
USART_Init(USART2, &usartInitStruct);
USART_Cmd(USART2, ENABLE); //使能串口
USART_ITConfig(USART2, USART_IT_RXNE, ENABLE); //使能接收中断
nvicInitStruct.NVIC_IRQChannel = USART2_IRQn;
nvicInitStruct.NVIC_IRQChannelCmd = ENABLE;
nvicInitStruct.NVIC_IRQChannelPreemptionPriority = 0;
nvicInitStruct.NVIC_IRQChannelSubPriority = 0;
NVIC_Init(&nvicInitStruct);
}

复制代码

调用DWM1000官方的API函数

int instance_run(void)
{
int instance = 0 ;
int done = INST_NOT_DONE_YET;
int message = instance_peekevent(); //get any of the received events from ISR
while(done == INST_NOT_DONE_YET)
{
//int state = instance_data[instance].testAppState;
done = testapprun(&instance_data[instance], message) ; // run the communications application
//we've processed message
message = 0;
}
if(done == INST_DONE_WAIT_FOR_NEXT_EVENT_TO) //we are in RX and need to timeout (Tag needs to send another poll if no Rx frame)
{
if(instance_data[instance].mode == TAG) //Tag (is either in RX or sleeping)
{
int32 nextPeriod ;
// next period will be a positive number because correction is -0.5 to +1.5 periods, (and tagSleepTime_ms is the period)
nextPeriod = instance_data[instance].tagSleepRnd + instance_data[instance].tagSleepTime_ms + instance_data[instance].tagSleepCorrection;
instance_data[instance].nextSleepPeriod = (uint32) nextPeriod ; //set timeout time, CAST the positive period to UINT for correct wrapping.
instance_data[instance].tagSleepCorrection2 = instance_data[instance].tagSleepCorrection;
instance_data[instance].tagSleepCorrection = 0; //clear the correction
instance_data[instance].instanceTimerEn = 1; //start timer
}
instance_data[instance].stopTimer = 0 ; //clear the flag - timer can run if instancetimer_en set (set above)
instance_data[instance].done = INST_NOT_DONE_YET;
}
//check if timer has expired
if((instance_data[instance].instanceTimerEn == 1) && (instance_data[instance].stopTimer == 0))
{
if(instance_data[instance].mode == TAG)
{
if((portGetTickCount() - instance_data[instance].instanceWakeTime) > instance_data[instance].nextSleepPeriod)
{
event_data_t dw_event;
instance_data[instance].instanceTimerEn = 0;
dw_event.rxLength = 0;
dw_event.type = 0;
dw_event.type_save = 0x80 | DWT_SIG_RX_TIMEOUT;
//printf("PC timeout DWT_SIG_RX_TIMEOUT\n");
instance_putevent(dw_event, DWT_SIG_RX_TIMEOUT);
}
}
#if (ANCTOANCTWR == 1) //allow anchor to anchor ranging
else if(instance_data[instance].mode == ANCHOR)
{
uint32_t slotTime = portGetTickCount() % instance_data[instance].sframePeriod;
if(instance_data[instance].gatewayAnchor)
{
//if we are in the last slot - then A0 ranges to A1 and A2
if( slotTime >= instance_data[instance].a0SlotTime)
{
port_DisableEXT_IRQ(); //enable ScenSor IRQ before starting
//anchor0 sends poll to anchor1
instance_data[instance].mode = ANCHOR_RNG; //change to ranging initiator
dwt_forcetrxoff(); //disable DW1000
instance_clearevents(); //clear any events
//change state to send a Poll
instance_data[instance].testAppState = TA_TXPOLL_WAIT_SEND ;
instance_data[instance].msg_f.destAddr[0] = 0x1 ;
instance_data[instance].msg_f.destAddr[1] = (GATEWAY_ANCHOR_ADDR >> 8);
instance_data[instance].instanceTimerEn = 0;
instance_data[instance].rangeNumAnc++;
port_EnableEXT_IRQ(); //enable ScenSor IRQ before starting
}
}
else if (instance_data[instance].instanceAddress16 == A1_ANCHOR_ADDR) //A1 ranges to A2 in the 2nd half of last slot
{
if(portGetTickCount() >= instance_data[instance].a1SlotTime)
{
port_DisableEXT_IRQ(); //enable ScenSor IRQ before starting
//anchor1 sends poll to anchor2
instance_data[instance].mode = ANCHOR_RNG; //change to ranging initiator
dwt_forcetrxoff(); //disable DW1000
instance_clearevents(); //clear any events
//change state to send a Poll
instance_data[instance].testAppState = TA_TXPOLL_WAIT_SEND ;
instance_data[instance].msg_f.destAddr[0] = 0x2 ;
instance_data[instance].msg_f.destAddr[1] = (GATEWAY_ANCHOR_ADDR >> 8);
instance_data[instance].instanceTimerEn = 0;
//instance_data[instance].a1SlotTime = 0;
port_EnableEXT_IRQ(); //enable ScenSor IRQ before starting
}
}
}
#endif
}
#if (ANCTOANCTWR == 1) //allow anchor to anchor ranging
else if (instance_data[instance].instanceTimerEn == 0)
{
if((instance_data[instance].mode == ANCHOR) && (instance_data[instance].gatewayAnchor))
{
uint32_t slotTime = portGetTickCount() % instance_data[instance].sframePeriod;
//enable the timer in 1st slot
if(slotTime < instance_data[instance].slotPeriod)
{
instance_data[instance].instanceTimerEn = 1;
}
}
}
#endif
return 0 ;
}

复制代码

三、硬件篇

2.1 硬件

DW1000是完全集成的单芯片超宽带（UWB）符合IEEE802.15.4-2011标准的低功耗低成本收发器IC。它可用于双向测距或TDOA定位系统定位,精度为10厘米。它还支持高达6.8 Mbps的数据传输,相关的原理图官网有详细说明。整个原理图我放在文文末，喜欢的可以回复下载。

通用软件：Altium Designer
主控芯片：nRF52832
通讯芯片：DWM1000

nRF52832外围原理图

DW1000外围原理图

2.2 丝印

如果有小伙伴不会制作logo的，这里把相关文件上传，以及“鹊桥”的丝印样板。

DXP-->Run Script-->Browse
选择目录D:\Altium Design\Examples\Scripts\Delphiscript Scripts\PCB\PCB Logo Creator
打开PCBLogoCreator.PRJSCR

效果图1

1

效果图2

Top Overlay

游客，如果您要查看本帖隐藏内容请回复

丝印.zip (45.23 KB, 下载次数: 11)

美好的一天 · 发表于 2019-8-8 10:02:31

期待

qiuxuezhe-14856 · 发表于 2019-8-9 12:39:58

厉害啊

xiaocaihong · 发表于 2019-8-9 13:06:04

优秀

AUST · 发表于 2019-8-10 11:53:13

xiaocaihong 发表于 2019-8-9 13:06
优秀

谢谢！

AUST · 发表于 2019-8-10 22:07:43

美好的一天发表于 2019-8-8 10:02
期待

后续有更新，谢谢关注！

⚡痛在⊙时刻⚡ · 发表于 2019-8-11 10:53:15

谢谢分享，学习了

AUST · 发表于 2019-8-11 15:27:36

qiuxuezhe-14856 发表于 2019-8-9 12:39
厉害啊

谢谢！

kunchen · 发表于 2019-8-11 16:49:34

谢谢

AUST · 发表于 2019-8-12 10:17:55

⚡痛在⊙时刻⚡ 发表于 2019-8-11 10:53
谢谢分享，学习了

共同学习，共同进步

[原创] 七夕鹊桥搭建-基于超宽带技术的心动“鹊桥”设计

站长推荐 /2