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Dependencies: General C12832 FatFileSystemCpp mbed
Fork of 1TestDECAWAVE_plus_others by
Diff: MM2WayRanging/MM2WayRanging.h
- Revision:
- 1:4523d7cda75e
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/MM2WayRanging/MM2WayRanging.h Fri Jun 17 20:35:28 2016 +0000 @@ -0,0 +1,97 @@ +// by Matthias Grob & Manuel Stalder - ETH Zürich - 2015 + +#ifndef MM2WAYRANGING_H +#define MM2WAYRANGING_H + +#include "mbed.h" +#include "DW1000.h" + +#define TIMEUNITS_TO_US (1/(128*499.2)) // conversion between the decawave timeunits (ca 15.65ps) to microseconds. +#define US_TO_TIMEUNITS (128*499.2) // conversion between microseconds to the decawave timeunits (ca 15.65ps). +#define MMRANGING_2POWER40 1099511627776 // decimal value of 2^40 to correct timeroverflow between timestamps + + + +//Predefined delay for the critical answers in the ranging algorithm +//HAS TO BE BIGGER THAN THE PROCESSING TIME OF THE FRAME ON THE NODE +#define ANSWER_DELAY_US 2500 //2500 works for 110kbps, 900 for 6.8Mbps +#define ANSWER_DELAY_TIMEUNITS ANSWER_DELAY_US * (128*499.2) + +class MM2WayRanging { + +public: + MM2WayRanging(DW1000& DW); + + void requestRanging(uint8_t destination); + void requestRangingAll(); + float rangeAndDisplayAll(); + char getStrength(); + + + + //TODO: Better capsulation on those? + bool isAnchor; + uint8_t address; // Identifies the nodes as source and destination in rangingframes + + //TODO: Make those PRIVATE! + float roundtriptimes[10]; // Array containing the round trip times to the anchors or the timeout which occured + float distances[10]; // Array containing the finally calculated Distances to the anchors + + bool overflow; // TRUE if counter overflows while ranging + +private: + + + DW1000& dw; + Timer LocalTimer; + + void callbackRX(); + void callbackTX(); + void sendPingFrame(uint8_t destination); + void sendDelayedAnswer(uint8_t destination, uint8_t type, uint64_t rxTimestamp); + void sendTransferFrame(uint8_t destination, int timestamp); + + inline float calibratedDistance(uint8_t destination); + + /** + * These two functions correct the timestamps if the counter had an overflow between measurements + */ + void correctReceiverTimestamps(uint8_t source); + void correctSenderTimestamps(uint8_t source); + + int timediffRec; + int timediffSend; + + enum FrameType{ + PING=1, + ANCHOR_RESPONSE, + BEACON_RESPONSE, + TRANSFER_FRAME, + DISTANCES_FRAME + }; + + //the packed attribute makes sure the types only use their respective size in memory (8 bit for uint8_t), otherwise they would always use 32 bit + //IT IS A GCC SPECIFIC DIRECTIVE + struct __attribute__((packed, aligned(1))) RangingFrame { + uint8_t source; + uint8_t destination; + uint8_t type; + }; + + struct __attribute__((packed, aligned(1))) ExtendedRangingFrame : RangingFrame{ + int signedTime; + }; + + + RangingFrame rangingFrame; // buffer in class for sending a frame (not made locally because then we can recall in the interrupt what was sent) + ExtendedRangingFrame transferFrame; + ExtendedRangingFrame receivedFrame; + uint64_t rxTimestamp; + uint64_t senderTimestamps[10][3]; + uint64_t receiverTimestamps[10][3]; + bool acknowledgement[10]; // flag to indicate if ranging has succeeded + uint32_t tofs[10]; // Array containing time of flights for each node (index is address of node) + +}; + +#endif