/*! ----------------------------------------------------------------------------
|
* @file main.c
|
* @brief Double-sided two-way ranging (DS TWR) initiator example code
|
*
|
* This is a simple code example which acts as the initiator in a DS TWR distance measurement exchange. This application sends a "poll"
|
* frame (recording the TX time-stamp of the poll), and then waits for a "response" message expected from the "DS TWR responder" example
|
* code (companion to this application). When the response is received its RX time-stamp is recorded and we send a "final" message to
|
* complete the exchange. The final message contains all the time-stamps recorded by this application, including the calculated/predicted TX
|
* time-stamp for the final message itself. The companion "DS TWR responder" example application works out the time-of-flight over-the-air
|
* and, thus, the estimated distance between the two devices.
|
*
|
* @attention
|
*
|
* Copyright 2015 (c) Decawave Ltd, Dublin, Ireland.
|
*
|
* All rights reserved.
|
*
|
* @author Decawave
|
*/
|
#include <string.h>
|
#include <stdio.h>
|
#include "deca_device_api.h"
|
#include "deca_regs.h"
|
#include "deca_sleep.h"
|
#include "lcd.h"
|
#include "port.h"
|
|
/* Example application name and version to display on LCD screen. */
|
#define APP_NAME "DS TWR INIT v1.1"
|
|
/* Inter-ranging delay period, in milliseconds. */
|
#define RNG_DELAY_MS 100
|
|
/* Default communication configuration. We use here EVK1000's default mode (mode 3). */
|
static dwt_config_t config = {
|
2, /* Channel number. */
|
DWT_PRF_64M, /* Pulse repetition frequency. */
|
DWT_PLEN_1024, /* Preamble length. */
|
DWT_PAC32, /* Preamble acquisition chunk size. Used in RX only. */
|
9, /* TX preamble code. Used in TX only. */
|
9, /* RX preamble code. Used in RX only. */
|
1, /* Use non-standard SFD (Boolean) */
|
DWT_BR_110K, /* Data rate. */
|
DWT_PHRMODE_STD, /* PHY header mode. */
|
(1025 + 64 - 32) /* SFD timeout (preamble length + 1 + SFD length - PAC size). Used in RX only. */
|
};
|
/* Default antenna delay values for 64 MHz PRF. See NOTE 1 below. */
|
#define TX_ANT_DLY 0
|
#define RX_ANT_DLY 32899
|
static uint8 rx_poll_msg[] = {0x00, 0x88, 0, 0xCA, 0xDE, 'W', 'A', 'V', 'E', 0x21, 0, 0};
|
static uint8 tx_resp_msg[] = {0x41, 0x88, 0, 0xCA, 0xDE, 'V', 'E', 'W', 'A', 0x10, 0x02, 0, 0, 0, 0};
|
static uint8 rx_final_msg[] = {0x41, 0x88, 0, 0xCA, 0xDE, 'W', 'A', 'V', 'E', 0x23, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
|
|
|
/* Frames used in the ranging process. See NOTE 2 below. */
|
static uint8 tx_poll_msg[] = {0x00, 0x88, 0, 0xCA, 0xDE, 'W', 'A', 'V', 'E', 0x21, 0, 0};
|
static uint8 rx_resp_msg[] = {0x41, 0x88, 0, 0xCA, 0xDE, 'V', 'E', 'W', 'A', 0x10, 0x02, 0, 0, 0, 0};
|
static uint8 tx_final_msg[] = {0x41, 0x88, 0, 0xCA, 0xDE, 'W', 'A', 'V', 'E', 0x23, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
|
/* Length of the common part of the message (up to and including the function code, see NOTE 2 below). */
|
typedef signed long long int64;
|
typedef unsigned long long uint64;
|
static uint64 poll_rx_ts;
|
static uint64 resp_tx_ts;
|
static uint64 final_rx_ts;
|
|
static double tof;
|
static double distance,dist2;
|
int16_t dist[8];
|
#define ALL_MSG_COMMON_LEN 10
|
/* Indexes to access some of the fields in the frames defined above. */
|
#define ALL_MSG_SN_IDX 2
|
#define FINAL_MSG_POLL_TX_TS_IDX 10
|
#define FINAL_MSG_RESP_RX_TS_IDX 14
|
#define FINAL_MSG_FINAL_TX_TS_IDX 18
|
#define FINAL_MSG_TS_LEN 4
|
/* Frame sequence number, incremented after each transmission. */
|
static uint32 frame_seq_nb = 0;
|
|
/* Buffer to store received response message.
|
* Its size is adjusted to longest frame that this example code is supposed to handle. */
|
#define RX_BUF_LEN 20
|
#define RX_BUF_LEN2 24
|
static uint8 rx_buffer[RX_BUF_LEN+4];
|
|
/* Hold copy of status register state here for reference, so reader can examine it at a breakpoint. */
|
static uint32 status_reg = 0;
|
|
/* UWB microsecond (uus) to device time unit (dtu, around 15.65 ps) conversion factor.
|
* 1 uus = 512 / 499.2 µs and 1 µs = 499.2 * 128 dtu. */
|
#define UUS_TO_DWT_TIME 65536
|
|
/* Delay between frames, in UWB microseconds. See NOTE 4 below. */
|
/* This is the delay from the end of the frame transmission to the enable of the receiver, as programmed for the DW1000's wait for response feature. */
|
#define POLL_TX_TO_RESP_RX_DLY_UUS 150
|
/* This is the delay from Frame RX timestamp to TX reply timestamp used for calculating/setting the DW1000's delayed TX function. This includes the
|
* frame length of approximately 2.66 ms with above configuration. */
|
#define RESP_RX_TO_FINAL_TX_DLY_UUS 4100
|
/* Receive response timeout. See NOTE 5 below. */
|
#define RESP_RX_TIMEOUT_UUS 14700
|
|
#define POLL_RX_TO_RESP_TX_DLY_UUS 3600
|
/* This is the delay from the end of the frame transmission to the enable of the receiver, as programmed for the DW1000's wait for response feature. */
|
#define RESP_TX_TO_FINAL_RX_DLY_UUS 500
|
/* Receive final timeout. See NOTE 5 below. */
|
#define FINAL_RX_TIMEOUT_UUS 4300
|
#define SPEED_OF_LIGHT 299702547
|
/* Time-stamps of frames transmission/reception, expressed in device time units.
|
* As they are 40-bit wide, we need to define a 64-bit int type to handle them. */
|
typedef unsigned long long uint64;
|
static uint64 poll_tx_ts;
|
static uint64 resp_rx_ts;
|
static uint64 final_tx_ts;
|
|
/* Declaration of static functions. */
|
static uint64 get_tx_timestamp_u64(void);
|
static uint64 get_rx_timestamp_u64(void);
|
static void final_msg_set_ts(uint8 *ts_field, uint64 ts);
|
|
/*! ------------------------------------------------------------------------------------------------------------------
|
* @fn main()
|
*
|
* @brief Application entry point.
|
*
|
* @param none
|
*
|
* @return none
|
*/
|
static void final_msg_get_ts(const uint8 *ts_field, uint32 *ts)
|
{
|
int i;
|
*ts = 0;
|
for (i = 0; i < FINAL_MSG_TS_LEN; i++)
|
{
|
*ts += ts_field[i] << (i * 8);
|
}
|
}
|
void GPIO_Toggle(GPIO_TypeDef* GPIOx, uint16_t GPIO_Pin)
|
{
|
GPIO_WriteBit(GPIOx, GPIO_Pin, (BitAction)!GPIO_ReadOutputDataBit(GPIOx, GPIO_Pin));
|
}
|
int fputc(int ch, FILE *f)
|
|
{
|
|
USART_SendData(USART1, (unsigned char) ch);// USART1 ???? USART2 ?
|
|
while (!(USART1->SR & USART_FLAG_TXE));
|
|
return (ch);
|
|
|
}
|
|
void USART_putc(char c)
|
{
|
//while(!(USART2->SR & 0x00000040));
|
//USART_SendData(USART2,c);
|
/* e.g. write a character to the USART */
|
USART_SendData(USART1, c);
|
|
/* Loop until the end of transmission */
|
while (USART_GetFlagStatus(USART1, USART_FLAG_TC) == RESET) ;
|
}
|
|
void USART_puts(uint8_t *s,uint8_t len)
|
{
|
int i;
|
for(i=0; i<len; i++)
|
{
|
USART_putc(s[i]);
|
}
|
}
|
int ld[100];
|
int LP(int tmp,uint8_t channel)
|
{
|
int data;
|
data = 0.7*ld[channel]+0.3*tmp;
|
ld[channel]=data;
|
return data;
|
}
|
uint16_t Checksum_u16(uint8_t* pdata, uint32_t len)
|
{
|
uint16_t sum = 0;
|
uint32_t i;
|
for(i=0; i<len; i++)
|
sum += pdata[i];
|
sum = ~sum;
|
return sum;
|
}
|
void LED_blink(void)
|
{
|
uint8_t ii;
|
for (ii=0;ii<10;ii++)
|
{
|
GPIO_Toggle(GPIOA,LED_PIN);
|
deca_sleep(100);
|
}
|
}
|
extern volatile unsigned long time32_reset;
|
extern uint8_t Work_Mode;
|
uint32 frame_len;
|
uint8_t send[9];
|
char dist_str[16] = {0};
|
int32_t dis;
|
double dID;
|
uint8_t TAG_ID,ANCHOR_ID, jumptime=0;
|
uint32_t rec_dist,hex_dist;
|
uint16_t check;
|
int main(void)
|
{
|
RCC_ClocksTypeDef RCC_Clocks; /* Start with board specific hardware init. */
|
peripherals_init();//³õʼ»¯ÍâÉè
|
RCC_GetClocksFreq(&RCC_Clocks);
|
/* Display application name on LCD. */
|
// lcd_display_str(APP_NAME);
|
|
/* Reset and initialise DW1000.
|
* For initialisation, DW1000 clocks must be temporarily set to crystal speed. After initialisation SPI rate can be increased for optimum
|
* performance. */
|
reset_DW1000();//ÖØÆôDW1000 /* Target specific drive of RSTn line into DW1000 low for a period. */
|
spi_set_rate_low();//½µµÍSPIƵÂÊ
|
dwt_initialise(DWT_LOADUCODE);//³õʼ»¯DW1000
|
spi_set_rate_high();//»Ø¸´SPIƵÂÊ
|
|
/* Configure DW1000. See NOTE 6 below. */
|
dwt_configure(&config);//ÅäÖÃDW1000
|
|
/* Apply default antenna delay value. See NOTE 1 below. */
|
dwt_setrxantennadelay(RX_ANT_DLY); //ÉèÖýÓÊÕÌìÏßÑÓ³Ù
|
dwt_settxantennadelay(TX_ANT_DLY); //ÉèÖ÷¢ÉäÌìÏßÑÓ³Ù
|
|
/* Set expected response's delay and timeout. See NOTE 4 and 5 below.
|
* As this example only handles one incoming frame with always the same delay and timeout, those values can be set here once for all. */
|
dwt_setrxaftertxdelay(POLL_TX_TO_RESP_RX_DLY_UUS);//ÉèÖ÷¢Ëͺó¿ªÆô½ÓÊÕ£¬²¢É趨ÑÓ³Ùʱ¼ä
|
dwt_setrxtimeout(RESP_RX_TIMEOUT_UUS); //ÉèÖýÓÊÕ³¬Ê±Ê±¼ä
|
|
send[0]=0x6D; //´®¿ÚÊý¾Ý
|
send[1]=0xD6; //´®¿ÚÊý¾Ý
|
|
tx_poll_msg[6] = ANCHOR_ID; //UWB POLL °üÊý¾Ý
|
rx_resp_msg[6] = ANCHOR_ID; //UWB RESPONSE °üÊý¾Ý
|
tx_final_msg[6] = ANCHOR_ID;//UWB Fianl °üÊý¾Ý
|
|
rx_poll_msg[6] = ANCHOR_ID;
|
tx_resp_msg[6] = ANCHOR_ID;
|
rx_final_msg[6] = ANCHOR_ID;
|
|
tx_poll_msg[5] = TAG_ID;//UWB POLL °üÊý¾Ý
|
rx_resp_msg[5] = TAG_ID;//UWB RESPONSE °üÊý¾Ý
|
tx_final_msg[5] = TAG_ID;//UWB Fianl °üÊý¾Ý
|
/* Loop forever initiating ranging exchanges. */
|
LED_blink();
|
if(!Work_Mode) //Ñ¡Ôñ·¢ËÍģʽ£¨TAG±êÇ©£©»¹ÊǽÓÊÕģʽ(ANCHOR»ùÕ¾)
|
{
|
while (1) //·¢ËÍģʽ(TAG±êÇ©)
|
{
|
/* Write frame data to DW1000 and prepare transmission. See NOTE 7 below. */
|
tx_poll_msg[ALL_MSG_SN_IDX] = frame_seq_nb;
|
dwt_writetxdata(sizeof(tx_poll_msg), tx_poll_msg, 0);//½«Poll°üÊý¾Ý´«¸øDW1000£¬½«ÔÚ¿ªÆô·¢ËÍʱ´«³öÈ¥
|
dwt_writetxfctrl(sizeof(tx_poll_msg), 0);//ÉèÖó¬¿í´ø·¢ËÍÊý¾Ý³¤¶È
|
|
/* Start transmission, indicating that a response is expected so that reception is enabled automatically after the frame is sent and the delay
|
* set by dwt_setrxaftertxdelay() has elapsed. */
|
dwt_starttx(DWT_START_TX_IMMEDIATE | DWT_RESPONSE_EXPECTED);//¿ªÆô·¢ËÍ£¬·¢ËÍÍê³ÉºóµÈ´ýÒ»¶Îʱ¼ä¿ªÆô½ÓÊÕ£¬µÈ´ýʱ¼äÔÚdwt_setrxaftertxdelayÖÐÉèÖÃ
|
|
/* We assume that the transmission is achieved correctly, poll for reception of a frame or error/timeout. See NOTE 8 below. */
|
while (!((status_reg = dwt_read32bitreg(SYS_STATUS_ID)) & (SYS_STATUS_RXFCG | SYS_STATUS_ALL_RX_ERR)))//²»¶Ï²éѯоƬ״ֱ̬µ½³É¹¦½ÓÊÕ»òÕß·¢Éú´íÎó
|
{ };
|
|
/* Increment frame sequence number after transmission of the poll message (modulo 256). */
|
frame_seq_nb++;
|
|
if (status_reg & SYS_STATUS_RXFCG)//Èç¹û³É¹¦½ÓÊÕ
|
{
|
uint32 frame_len;
|
|
/* Clear good RX frame event and TX frame sent in the DW1000 status register. */
|
dwt_write32bitreg(SYS_STATUS_ID, SYS_STATUS_RXFCG | SYS_STATUS_TXFRS);//Çå³þ¼Ä´æÆ÷±ê־λ
|
|
/* A frame has been received, read it into the local buffer. */
|
frame_len = dwt_read32bitreg(RX_FINFO_ID) & RX_FINFO_RXFLEN_MASK; //»ñµÃ½ÓÊÕµ½µÄÊý¾Ý³¤¶È
|
|
dwt_readrxdata(rx_buffer, frame_len, 0); //¶ÁÈ¡½ÓÊÕÊý¾Ý
|
|
|
/* Check that the frame is the expected response from the companion "DS TWR responder" example.
|
* As the sequence number field of the frame is not relevant, it is cleared to simplify the validation of the frame. */
|
rx_buffer[ALL_MSG_SN_IDX] = 0;
|
if (rx_buffer[9]==0x10)//ÅжϽÓÊÕµ½µÄÊý¾ÝÊÇ·ñÊÇresponseÊý¾Ý
|
{
|
uint32 final_tx_time;
|
|
|
/* Retrieve poll transmission and response reception timestamp. */
|
poll_tx_ts = get_tx_timestamp_u64(); //»ñµÃPOLL·¢ËÍʱ¼äT1
|
resp_rx_ts = get_rx_timestamp_u64(); //»ñµÃRESPONSE½ÓÊÕʱ¼äT4
|
|
memcpy(&dist[TAG_ID],&rx_buffer[11],2);
|
|
/* Compute final message transmission time. See NOTE 9 below. */
|
final_tx_time = (resp_rx_ts + (RESP_RX_TO_FINAL_TX_DLY_UUS * UUS_TO_DWT_TIME)) >> 8;//¼ÆËãfinal°ü·¢ËÍʱ¼ä£¬T5=T4+Treply2
|
dwt_setdelayedtrxtime(final_tx_time);//ÉèÖÃfinal°ü·¢ËÍʱ¼äT5
|
|
/* Final TX timestamp is the transmission time we programmed plus the TX antenna delay. */
|
final_tx_ts = (((uint64)(final_tx_time & 0xFFFFFFFE)) << 8) + TX_ANT_DLY;//final°üʵ¼Ê·¢ËÍʱ¼äÊǼÆËãʱ¼ä¼ÓÉÏ·¢ËÍÌìÏßdelay
|
|
/* Write all timestamps in the final message. See NOTE 10 below. */
|
final_msg_set_ts(&tx_final_msg[FINAL_MSG_POLL_TX_TS_IDX], poll_tx_ts);//½«T1£¬T4£¬T5дÈë·¢ËÍÊý¾Ý
|
final_msg_set_ts(&tx_final_msg[FINAL_MSG_RESP_RX_TS_IDX], resp_rx_ts);
|
final_msg_set_ts(&tx_final_msg[FINAL_MSG_FINAL_TX_TS_IDX], final_tx_ts);
|
|
/* Write and send final message. See NOTE 7 below. */
|
tx_final_msg[ALL_MSG_SN_IDX] = frame_seq_nb;
|
dwt_writetxdata(sizeof(tx_final_msg), tx_final_msg, 0);//½«·¢ËÍÊý¾ÝдÈëDW1000
|
dwt_writetxfctrl(sizeof(tx_final_msg), 0);//É趨·¢ËÍÊý¾Ý³¤¶È
|
dwt_starttx(DWT_START_TX_DELAYED);//É趨ΪÑÓ³Ù·¢ËÍ
|
|
if (GPIO_ReadInputDataBit(GPIOA,SW2) != RESET) //ͨ¹ý²¦Â뿪¹ØÅжÏÊý¾ÝÊä³ö¸ñʽ
|
{
|
dID=TAG_ID;
|
printf("TAG_ID: %2.0f ", dID);
|
dID=ANCHOR_ID;
|
printf("ANCHOR_ID: %2.0f ", dID);
|
printf("Distance: %5.0f cm\n", (double)dist[TAG_ID]);
|
}else{
|
send[2] = ANCHOR_ID;
|
send[3] = TAG_ID;
|
|
memcpy(&send[4],&dist[TAG_ID],2);
|
check=Checksum_u16(&send[2],6);
|
memcpy(&send[8],&check,2);
|
USART_puts(send,10);
|
}
|
/* Poll DW1000 until TX frame sent event set. See NOTE 8 below. */
|
while (!(dwt_read32bitreg(SYS_STATUS_ID) & SYS_STATUS_TXFRS))//²»¶Ï²éѯоƬ״ֱ̬µ½·¢ËÍÍê³É
|
{ };
|
|
/* Clear TXFRS event. */
|
dwt_write32bitreg(SYS_STATUS_ID, SYS_STATUS_TXFRS);//Çå³þ±ê־λ
|
|
/* Increment frame sequence number after transmission of the final message (modulo 256). */
|
frame_seq_nb++;
|
time32_reset = 0;
|
GPIO_Toggle(GPIOA,LED_PIN);//LEDÉÁ˸
|
jumptime = 0;
|
}else{
|
jumptime =5;//Èç¹ûͨѶʧ°Ü£¬½«¼ä¸ôʱ¼äÔö¼Ó5ms£¬±Ü¿ªÒòΪ¶à±êǩͬʱ·¢ËÍÒýÆðµÄ³åÍ»¡£
|
}
|
}
|
else
|
{
|
/* Clear RX error events in the DW1000 status register. */
|
dwt_write32bitreg(SYS_STATUS_ID, SYS_STATUS_ALL_RX_ERR);
|
jumptime =5;
|
}
|
|
/* Execute a delay between ranging exchanges. */
|
deca_sleep(RNG_DELAY_MS+jumptime);//ÐÝÃ߹̶¨Ê±¼ä
|
}
|
}else{
|
while (1)//½ÓÊÕģʽ(ANCHOR»ùÕ¾)
|
{
|
/* Clear reception timeout to start next ranging process. */
|
dwt_setrxtimeout(0);//É趨½ÓÊÕ³¬Ê±Ê±¼ä£¬0λûÓг¬Ê±Ê±¼ä
|
|
/* Activate reception immediately. */
|
dwt_rxenable(0);//´ò¿ª½ÓÊÕ
|
|
/* Poll for reception of a frame or error/timeout. See NOTE 7 below. */
|
while (!((status_reg = dwt_read32bitreg(SYS_STATUS_ID)) & (SYS_STATUS_RXFCG | SYS_STATUS_ALL_RX_ERR)))//²»¶Ï²éѯоƬ״ֱ̬µ½½ÓÊճɹ¦»òÕß³öÏÖ´íÎó
|
{ };
|
|
if (status_reg & SYS_STATUS_RXFCG)//³É¹¦½ÓÊÕ
|
{
|
|
|
/* Clear good RX frame event in the DW1000 status register. */
|
dwt_write32bitreg(SYS_STATUS_ID, SYS_STATUS_RXFCG);//Çå³þ±ê־λ
|
|
/* A frame has been received, read it into the local buffer. */
|
frame_len = dwt_read32bitreg(RX_FINFO_ID) & RX_FINFO_RXFL_MASK_1023;//»ñµÃ½ÓÊÕÊý¾Ý³¤¶È
|
|
dwt_readrxdata(rx_buffer, frame_len, 0);//¶ÁÈ¡½ÓÊÕÊý¾Ý
|
|
|
/* Check that the frame is a poll sent by "DS TWR initiator" example.
|
* As the sequence number field of the frame is not relevant, it is cleared to simplify the validation of the frame. */
|
rx_buffer[ALL_MSG_SN_IDX] = 0;
|
TAG_ID = rx_buffer[5];
|
rx_poll_msg[5] = TAG_ID;//Ϊ¶à±êǩͨѶ·þÎñ£¬·ÀÖ¹Ò»´ÎͨѶÖнÓÊÕµ½²»Í¬ID±êÇ©µÄÊý¾Ý
|
tx_resp_msg[5] = TAG_ID;
|
rx_final_msg[5] = TAG_ID;
|
if (rx_buffer[9]==0x21)//ÅжÏÊÇ·ñÊÇpoll°üÊý¾Ý
|
{
|
uint32 resp_tx_time;
|
|
/* Retrieve poll reception timestamp. */
|
poll_rx_ts = get_rx_timestamp_u64();//»ñµÃPoll°ü½ÓÊÕʱ¼äT2
|
|
/* Set send time for response. See NOTE 8 below. */
|
resp_tx_time = (poll_rx_ts + (POLL_RX_TO_RESP_TX_DLY_UUS * UUS_TO_DWT_TIME)) >> 8;//¼ÆËãResponse·¢ËÍʱ¼äT3¡£
|
dwt_setdelayedtrxtime(resp_tx_time);//ÉèÖÃResponse·¢ËÍʱ¼äT3
|
|
/* Set expected delay and timeout for final message reception. */
|
dwt_setrxaftertxdelay(RESP_TX_TO_FINAL_RX_DLY_UUS);//ÉèÖ÷¢ËÍÍê³Éºó¿ªÆô½ÓÊÕÑÓ³Ùʱ¼ä
|
dwt_setrxtimeout(FINAL_RX_TIMEOUT_UUS);//½ÓÊÕ³¬Ê±Ê±¼ä
|
|
/* Write and send the response message. See NOTE 9 below.*/
|
memcpy(&tx_resp_msg[11],&dist[TAG_ID],2);
|
tx_resp_msg[ALL_MSG_SN_IDX] = frame_seq_nb;
|
dwt_writetxdata(sizeof(tx_resp_msg), tx_resp_msg, 0);//дÈë·¢ËÍÊý¾Ý
|
dwt_writetxfctrl(sizeof(tx_resp_msg), 0);//É趨·¢Ëͳ¤¶È
|
dwt_starttx(DWT_START_TX_DELAYED | DWT_RESPONSE_EXPECTED);//ÑÓ³Ù·¢ËÍ£¬µÈ´ý½ÓÊÕ
|
|
/* We assume that the transmission is achieved correctly, now poll for reception of expected "final" frame or error/timeout.
|
* See NOTE 7 below. */
|
while (!((status_reg = dwt_read32bitreg(SYS_STATUS_ID)) & (SYS_STATUS_RXFCG | SYS_STATUS_ALL_RX_ERR)))///²»¶Ï²éѯоƬ״ֱ̬µ½½ÓÊճɹ¦»òÕß³öÏÖ´íÎó
|
{ };
|
|
/* Increment frame sequence number after transmission of the response message (modulo 256). */
|
frame_seq_nb++;
|
|
if (status_reg & SYS_STATUS_RXFCG)//½ÓÊճɹ¦
|
{
|
/* Clear good RX frame event and TX frame sent in the DW1000 status register. */
|
dwt_write32bitreg(SYS_STATUS_ID, SYS_STATUS_RXFCG | SYS_STATUS_TXFRS);//Çå³þ±ê־λ
|
|
/* A frame has been received, read it into the local buffer. */
|
frame_len = dwt_read32bitreg(RX_FINFO_ID) & RX_FINFO_RXFLEN_MASK;//Êý¾Ý³¤¶È
|
|
dwt_readrxdata(rx_buffer, frame_len, 0);//¶ÁÈ¡½ÓÊÕÊý¾Ý
|
|
|
/* Check that the frame is a final message sent by "DS TWR initiator" example.
|
* As the sequence number field of the frame is not used in this example, it can be zeroed to ease the validation of the frame. */
|
rx_buffer[ALL_MSG_SN_IDX] = 0;
|
if (rx_buffer[9]==0x23)//ÅжÏÊÇ·ñΪFianl°ü
|
{
|
uint32 poll_tx_ts, resp_rx_ts, final_tx_ts;
|
uint32 poll_rx_ts_32, resp_tx_ts_32, final_rx_ts_32;
|
double Ra, Rb, Da, Db;
|
int64 tof_dtu;
|
|
/* Retrieve response transmission and final reception timestamps. */
|
resp_tx_ts = get_tx_timestamp_u64();//»ñµÃresponse·¢ËÍʱ¼äT3
|
final_rx_ts = get_rx_timestamp_u64();//»ñµÃfinal½ÓÊÕʱ¼äT6
|
|
/* Get timestamps embedded in the final message. */
|
final_msg_get_ts(&rx_buffer[FINAL_MSG_POLL_TX_TS_IDX], &poll_tx_ts);//´Ó½ÓÊÕÊý¾ÝÖжÁÈ¡T1£¬T4£¬T5
|
final_msg_get_ts(&rx_buffer[FINAL_MSG_RESP_RX_TS_IDX], &resp_rx_ts);
|
final_msg_get_ts(&rx_buffer[FINAL_MSG_FINAL_TX_TS_IDX], &final_tx_ts);
|
|
/* Compute time of flight. 32-bit subtractions give correct answers even if clock has wrapped. See NOTE 10 below. */
|
poll_rx_ts_32 = (uint32)poll_rx_ts;//ʹÓÃ32λÊý¾Ý¼ÆËã
|
resp_tx_ts_32 = (uint32)resp_tx_ts;
|
final_rx_ts_32 = (uint32)final_rx_ts;
|
Ra = (double)(resp_rx_ts - poll_tx_ts);//Tround1 = T4 - T1
|
Rb = (double)(final_rx_ts_32 - resp_tx_ts_32);//Tround2 = T6 - T3
|
Da = (double)(final_tx_ts - resp_rx_ts);//Treply2 = T5 - T4
|
Db = (double)(resp_tx_ts_32 - poll_rx_ts_32);//Treply1 = T3 - T2
|
tof_dtu = (int64)((Ra * Rb - Da * Db) / (Ra + Rb + Da + Db));//¼ÆË㹫ʽ
|
|
tof = tof_dtu * DWT_TIME_UNITS;
|
distance = tof * SPEED_OF_LIGHT;//¾àÀë=¹âËÙ*·ÉÐÐʱ¼ä
|
dist2 = distance - dwt_getrangebias(config.chan,(float)distance, config.prf);//¾àÀë¼õÈ¥½ÃÕýϵÊý
|
|
dis = dist2*100;//dis Ϊµ¥Î»ÎªcmµÄ¾àÀë
|
dist[TAG_ID] = LP(dis,TAG_ID);//LP ΪµÍͨÂ˲¨Æ÷£¬ÈÃÊý¾Ý¸üÎȶ¨
|
time32_reset = 0;
|
GPIO_Toggle(GPIOA,LED_PIN);
|
if (GPIO_ReadInputDataBit(GPIOA,SW2) != RESET) //ͨ¹ý²¦Â뿪¹ØÅжÏÊý¾ÝÊä³ö¸ñʽ
|
{
|
dID=TAG_ID;
|
printf("TAG_ID: %2.0f ", dID);
|
dID=ANCHOR_ID;
|
printf("ANCHOR_ID: %2.0f ", dID);
|
printf("Distance: %5.0f cm\n", (double)dist[TAG_ID]);
|
}else{
|
send[2] = ANCHOR_ID;
|
send[3] = TAG_ID;
|
|
memcpy(&send[4],&dist[TAG_ID],2);
|
check=Checksum_u16(&send[2],6);
|
memcpy(&send[8],&check,2);
|
USART_puts(send,10);
|
}
|
|
}
|
}
|
else
|
{
|
/* Clear RX error events in the DW1000 status register. */
|
dwt_write32bitreg(SYS_STATUS_ID, SYS_STATUS_ALL_RX_ERR);
|
}
|
}
|
}
|
else
|
{
|
/* Clear RX error events in the DW1000 status register. */
|
dwt_write32bitreg(SYS_STATUS_ID, SYS_STATUS_ALL_RX_ERR);
|
}
|
}
|
|
|
}
|
}
|
|
/*! ------------------------------------------------------------------------------------------------------------------
|
* @fn get_tx_timestamp_u64()
|
*
|
* @brief Get the TX time-stamp in a 64-bit variable.
|
* /!\ This function assumes that length of time-stamps is 40 bits, for both TX and RX!
|
*
|
* @param none
|
*
|
* @return 64-bit value of the read time-stamp.
|
*/
|
static uint64 get_tx_timestamp_u64(void)
|
{
|
uint8 ts_tab[5];
|
uint64 ts = 0;
|
int i;
|
dwt_readtxtimestamp(ts_tab);
|
for (i = 4; i >= 0; i--)
|
{
|
ts <<= 8;
|
ts |= ts_tab[i];
|
}
|
return ts;
|
}
|
|
/*! ------------------------------------------------------------------------------------------------------------------
|
* @fn get_rx_timestamp_u64()
|
*
|
* @brief Get the RX time-stamp in a 64-bit variable.
|
* /!\ This function assumes that length of time-stamps is 40 bits, for both TX and RX!
|
*
|
* @param none
|
*
|
* @return 64-bit value of the read time-stamp.
|
*/
|
static uint64 get_rx_timestamp_u64(void)
|
{
|
uint8 ts_tab[5];
|
uint64 ts = 0;
|
int i;
|
dwt_readrxtimestamp(ts_tab);
|
for (i = 4; i >= 0; i--)
|
{
|
ts <<= 8;
|
ts |= ts_tab[i];
|
}
|
return ts;
|
}
|
|
/*! ------------------------------------------------------------------------------------------------------------------
|
* @fn final_msg_set_ts()
|
*
|
* @brief Fill a given timestamp field in the final message with the given value. In the timestamp fields of the final
|
* message, the least significant byte is at the lower address.
|
*
|
* @param ts_field pointer on the first byte of the timestamp field to fill
|
* ts timestamp value
|
*
|
* @return none
|
*/
|
static void final_msg_set_ts(uint8 *ts_field, uint64 ts)
|
{
|
int i;
|
for (i = 0; i < FINAL_MSG_TS_LEN; i++)
|
{
|
ts_field[i] = (uint8) ts;
|
ts >>= 8;
|
}
|
}
|
|
/*****************************************************************************************************************************************************
|
* NOTES:
|
*
|
* 1. The sum of the values is the TX to RX antenna delay, experimentally determined by a calibration process. Here we use a hard coded typical value
|
* but, in a real application, each device should have its own antenna delay properly calibrated to get the best possible precision when performing
|
* range measurements.
|
* 2. The messages here are similar to those used in the DecaRanging ARM application (shipped with EVK1000 kit). They comply with the IEEE
|
* 802.15.4 standard MAC data frame encoding and they are following the ISO/IEC:24730-62:2013 standard. The messages used are:
|
* - a poll message sent by the initiator to trigger the ranging exchange.
|
* - a response message sent by the responder allowing the initiator to go on with the process
|
* - a final message sent by the initiator to complete the exchange and provide all information needed by the responder to compute the
|
* time-of-flight (distance) estimate.
|
* The first 10 bytes of those frame are common and are composed of the following fields:
|
* - byte 0/1: frame control (0x8841 to indicate a data frame using 16-bit addressing).
|
* - byte 2: sequence number, incremented for each new frame.
|
* - byte 3/4: PAN TAG_ID (0xDECA).
|
* - byte 5/6: destination address, see NOTE 3 below.
|
* - byte 7/8: source address, see NOTE 3 below.
|
* - byte 9: function code (specific values to indicate which message it is in the ranging process).
|
* The remaining bytes are specific to each message as follows:
|
* Poll message:
|
* - no more data
|
* Response message:
|
* - byte 10: activity code (0x02 to tell the initiator to go on with the ranging exchange).
|
* - byte 11/12: activity parameter, not used here for activity code 0x02.
|
* Final message:
|
* - byte 10 -> 13: poll message transmission timestamp.
|
* - byte 14 -> 17: response message reception timestamp.
|
* - byte 18 -> 21: final message transmission timestamp.
|
* All messages end with a 2-byte checksum automatically set by DW1000.
|
* 3. Source and destination addresses are hard coded constants in this example to keep it simple but for a real product every device should have a
|
* unique TAG_ID. Here, 16-bit addressing is used to keep the messages as short as possible but, in an actual application, this should be done only
|
* after an exchange of specific messages used to define those short addresses for each device participating to the ranging exchange.
|
* 4. Delays between frames have been chosen here to ensure proper synchronisation of transmission and reception of the frames between the initiator
|
* and the responder and to ensure a correct accuracy of the computed distance. The user is referred to DecaRanging ARM Source Code Guide for more
|
* details about the timings involved in the ranging process.
|
* 5. This timeout is for complete reception of a frame, i.e. timeout duration must take into account the length of the expected frame. Here the value
|
* is arbitrary but chosen large enough to make sure that there is enough time to receive the complete response frame sent by the responder at the
|
* 110k data rate used (around 3 ms).
|
* 6. In a real application, for optimum performance within regulatory limits, it may be necessary to set TX pulse bandwidth and TX power, (using
|
* the dwt_configuretxrf API call) to per device calibrated values saved in the target system or the DW1000 OTP memory.
|
* 7. dwt_writetxdata() takes the full size of the message as a parameter but only copies (size - 2) bytes as the check-sum at the end of the frame is
|
* automatically appended by the DW1000. This means that our variable could be two bytes shorter without losing any data (but the sizeof would not
|
* work anymore then as we would still have to indicate the full length of the frame to dwt_writetxdata()). It is also to be noted that, when using
|
* delayed send, the time set for transmission must be far enough in the future so that the DW1000 IC has the time to process and start the
|
* transmission of the frame at the wanted time. If the transmission command is issued too late compared to when the frame is supposed to be sent,
|
* this is indicated by an error code returned by dwt_starttx() API call. Here it is not tested, as the values of the delays between frames have
|
* been carefully defined to avoid this situation.
|
* 8. We use polled mode of operation here to keep the example as simple as possible but all status events can be used to generate interrupts. Please
|
* refer to DW1000 User Manual for more details on "interrupts". It is also to be noted that STATUS register is 5 bytes long but, as the event we
|
* use are all in the first bytes of the register, we can use the simple dwt_read32bitreg() API call to access it instead of reading the whole 5
|
* bytes.
|
* 9. As we want to send final TX timestamp in the final message, we have to compute it in advance instead of relying on the reading of DW1000
|
* register. Timestamps and delayed transmission time are both expressed in device time units so we just have to add the desired response delay to
|
* response RX timestamp to get final transmission time. The delayed transmission time resolution is 512 device time units which means that the
|
* lower 9 bits of the obtained value must be zeroed. This also allows to encode the 40-bit value in a 32-bit words by shifting the all-zero lower
|
* 8 bits.
|
* 10. In this operation, the high order byte of each 40-bit timestamps is discarded. This is acceptable as those time-stamps are not separated by
|
* more than 2**32 device time units (which is around 67 ms) which means that the calculation of the round-trip delays (needed in the
|
* time-of-flight computation) can be handled by a 32-bit subtraction.
|
* 11. The user is referred to DecaRanging ARM application (distributed with EVK1000 product) for additional practical example of usage, and to the
|
* DW1000 API Guide for more details on the DW1000 driver functions.
|
****************************************************************************************************************************************************/
|
