Library for HopeRF RFM22 / RFM22B transceiver module ported to mbed. Original Software from Mike McCauley (mikem@open.com.au) . See http://www.open.com.au/mikem/arduino/RF22/
Dependents: RF22_MAX_test_Send Geofence_receiver Geofence_sender Geofence_sender ... more
More Info about RFM22-modules like connecting and a demo-program see RF22-Notebook
RF22ReliableDatagram.cpp@1:813d4f57d630, 2012-02-17 (annotated)
- Committer:
- charly
- Date:
- Fri Feb 17 21:40:57 2012 +0000
- Revision:
- 1:813d4f57d630
- Parent:
- 0:79c6d0071c4c
- Child:
- 5:0386600f3408
fixed use of rand() in ReliableDatagram
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
charly | 0:79c6d0071c4c | 1 | // RF22ReliableDatagram.cpp |
charly | 0:79c6d0071c4c | 2 | // |
charly | 0:79c6d0071c4c | 3 | // Define addressed datagram |
charly | 1:813d4f57d630 | 4 | // |
charly | 1:813d4f57d630 | 5 | // Part of the Arduino RF22 library for operating with HopeRF RF22 compatible transceivers |
charly | 0:79c6d0071c4c | 6 | // (see http://www.hoperf.com) |
charly | 1:813d4f57d630 | 7 | // RF22Datagram will be received only by the addressed node or all nodes within range if the |
charly | 0:79c6d0071c4c | 8 | // to address is RF22_BROADCAST_ADDRESS |
charly | 0:79c6d0071c4c | 9 | // |
charly | 0:79c6d0071c4c | 10 | // Author: Mike McCauley (mikem@open.com.au) |
charly | 0:79c6d0071c4c | 11 | // Copyright (C) 2011 Mike McCauley |
charly | 0:79c6d0071c4c | 12 | // $Id: RF22ReliableDatagram.cpp,v 1.8 2011/02/15 01:18:03 mikem Exp $ |
charly | 0:79c6d0071c4c | 13 | // ported to mbed by Karl Zweimueller |
charly | 0:79c6d0071c4c | 14 | |
charly | 0:79c6d0071c4c | 15 | #include <RF22ReliableDatagram.h> |
charly | 0:79c6d0071c4c | 16 | //#include <SPI.h> |
charly | 0:79c6d0071c4c | 17 | |
charly | 0:79c6d0071c4c | 18 | |
charly | 0:79c6d0071c4c | 19 | //////////////////////////////////////////////////////////////////// |
charly | 0:79c6d0071c4c | 20 | // Constructors |
charly | 1:813d4f57d630 | 21 | RF22ReliableDatagram::RF22ReliableDatagram(uint8_t thisAddress ,PinName slaveSelectPin , PinName mosi, PinName miso, PinName sclk, PinName interrupt ) |
charly | 1:813d4f57d630 | 22 | : RF22Datagram(thisAddress ,slaveSelectPin , mosi, miso, sclk, interrupt ) { |
charly | 0:79c6d0071c4c | 23 | _retransmissions = 0; |
charly | 0:79c6d0071c4c | 24 | _lastSequenceNumber = 0; |
charly | 0:79c6d0071c4c | 25 | _timeout = 200; |
charly | 0:79c6d0071c4c | 26 | _retries = 3; |
charly | 0:79c6d0071c4c | 27 | } |
charly | 0:79c6d0071c4c | 28 | |
charly | 0:79c6d0071c4c | 29 | //////////////////////////////////////////////////////////////////// |
charly | 0:79c6d0071c4c | 30 | // Public methods |
charly | 1:813d4f57d630 | 31 | void RF22ReliableDatagram::setTimeout(uint16_t timeout) { |
charly | 0:79c6d0071c4c | 32 | _timeout = timeout; |
charly | 0:79c6d0071c4c | 33 | } |
charly | 0:79c6d0071c4c | 34 | |
charly | 0:79c6d0071c4c | 35 | //////////////////////////////////////////////////////////////////// |
charly | 1:813d4f57d630 | 36 | void RF22ReliableDatagram::setRetries(uint8_t retries) { |
charly | 0:79c6d0071c4c | 37 | _retries = retries; |
charly | 0:79c6d0071c4c | 38 | } |
charly | 0:79c6d0071c4c | 39 | |
charly | 0:79c6d0071c4c | 40 | //////////////////////////////////////////////////////////////////// |
charly | 1:813d4f57d630 | 41 | boolean RF22ReliableDatagram::sendtoWait(uint8_t* buf, uint8_t len, uint8_t address) { |
charly | 0:79c6d0071c4c | 42 | // Assemble the message |
charly | 0:79c6d0071c4c | 43 | uint8_t thisSequenceNumber = ++_lastSequenceNumber; |
charly | 0:79c6d0071c4c | 44 | |
charly | 0:79c6d0071c4c | 45 | Timer t; |
charly | 1:813d4f57d630 | 46 | |
charly | 0:79c6d0071c4c | 47 | uint8_t retries = 0; |
charly | 1:813d4f57d630 | 48 | while (retries++ <= _retries) { |
charly | 1:813d4f57d630 | 49 | setHeaderId(thisSequenceNumber); |
charly | 1:813d4f57d630 | 50 | setHeaderFlags(0); |
charly | 1:813d4f57d630 | 51 | sendto(buf, len, address); |
charly | 1:813d4f57d630 | 52 | waitPacketSent(); |
charly | 0:79c6d0071c4c | 53 | |
charly | 1:813d4f57d630 | 54 | // Never wait for ACKS to broadcasts: |
charly | 1:813d4f57d630 | 55 | if (address == RF22_BROADCAST_ADDRESS) |
charly | 1:813d4f57d630 | 56 | return true; |
charly | 0:79c6d0071c4c | 57 | |
charly | 1:813d4f57d630 | 58 | if (retries > 1) |
charly | 1:813d4f57d630 | 59 | _retransmissions++; |
charly | 1:813d4f57d630 | 60 | t.start(); |
charly | 1:813d4f57d630 | 61 | unsigned long thisSendTime = t.read_ms(); // Timeout does not include original transmit time |
charly | 0:79c6d0071c4c | 62 | |
charly | 0:79c6d0071c4c | 63 | |
charly | 1:813d4f57d630 | 64 | // Compute a new timeout, random between _timeout and _timeout*2 |
charly | 1:813d4f57d630 | 65 | // This is to prevent collissions on every retransmit |
charly | 1:813d4f57d630 | 66 | // if 2 nodes try to transmit at the same time |
charly | 1:813d4f57d630 | 67 | uint16_t timeout = _timeout + (_timeout * (rand() % 100) / 100); |
charly | 1:813d4f57d630 | 68 | while (t.read_ms() < (thisSendTime + timeout)) { |
charly | 1:813d4f57d630 | 69 | if (available()) { |
charly | 1:813d4f57d630 | 70 | clearRxBuf(); // Not using recv, so clear it ourselves |
charly | 1:813d4f57d630 | 71 | uint8_t from = headerFrom(); |
charly | 1:813d4f57d630 | 72 | uint8_t to = headerTo(); |
charly | 1:813d4f57d630 | 73 | uint8_t id = headerId(); |
charly | 1:813d4f57d630 | 74 | uint8_t flags = headerFlags(); |
charly | 1:813d4f57d630 | 75 | // Now have a message: is it our ACK? |
charly | 1:813d4f57d630 | 76 | if ( from == address |
charly | 1:813d4f57d630 | 77 | && to == _thisAddress |
charly | 1:813d4f57d630 | 78 | && (flags & RF22_FLAGS_ACK) |
charly | 1:813d4f57d630 | 79 | && (id == thisSequenceNumber)) { |
charly | 1:813d4f57d630 | 80 | // Its the ACK we are waiting for |
charly | 1:813d4f57d630 | 81 | return true; |
charly | 1:813d4f57d630 | 82 | } else if ( !(flags & RF22_FLAGS_ACK) |
charly | 1:813d4f57d630 | 83 | && (id == _seenIds[from])) { |
charly | 1:813d4f57d630 | 84 | // This is a request we have already received. ACK it again |
charly | 1:813d4f57d630 | 85 | acknowledge(id, from); |
charly | 1:813d4f57d630 | 86 | } |
charly | 1:813d4f57d630 | 87 | // Else discard it |
charly | 1:813d4f57d630 | 88 | } |
charly | 1:813d4f57d630 | 89 | // Not the one we are waiting for, maybe keep waiting until timeout exhausted |
charly | 0:79c6d0071c4c | 90 | } |
charly | 1:813d4f57d630 | 91 | // Timeout exhausted, maybe retry |
charly | 0:79c6d0071c4c | 92 | } |
charly | 0:79c6d0071c4c | 93 | return false; |
charly | 0:79c6d0071c4c | 94 | } |
charly | 0:79c6d0071c4c | 95 | |
charly | 0:79c6d0071c4c | 96 | //////////////////////////////////////////////////////////////////// |
charly | 1:813d4f57d630 | 97 | boolean RF22ReliableDatagram::recvfromAck(uint8_t* buf, uint8_t* len, uint8_t* from, uint8_t* to, uint8_t* id, uint8_t* flags) { |
charly | 0:79c6d0071c4c | 98 | uint8_t _from; |
charly | 0:79c6d0071c4c | 99 | uint8_t _to; |
charly | 0:79c6d0071c4c | 100 | uint8_t _id; |
charly | 0:79c6d0071c4c | 101 | uint8_t _flags; |
charly | 0:79c6d0071c4c | 102 | // Get the message before its clobbered by the ACK (shared rx anfd tx buffer in RF22 |
charly | 1:813d4f57d630 | 103 | if (available() && recvfrom(buf, len, &_from, &_to, &_id, &_flags)) { |
charly | 1:813d4f57d630 | 104 | // Never ACK an ACK |
charly | 1:813d4f57d630 | 105 | if (!(_flags & RF22_FLAGS_ACK)) { |
charly | 1:813d4f57d630 | 106 | // Its a normal message for this node, not an ACK |
charly | 1:813d4f57d630 | 107 | if (_to != RF22_BROADCAST_ADDRESS) { |
charly | 1:813d4f57d630 | 108 | // Its not a broadcast, so ACK it |
charly | 1:813d4f57d630 | 109 | // Acknowledge message with ACK set in flags and ID set to received ID |
charly | 1:813d4f57d630 | 110 | acknowledge(_id, _from); |
charly | 1:813d4f57d630 | 111 | } |
charly | 1:813d4f57d630 | 112 | // If we have not seen this message before, then we are interested in it |
charly | 1:813d4f57d630 | 113 | if (_id != _seenIds[_from]) { |
charly | 1:813d4f57d630 | 114 | if (from) *from = _from; |
charly | 1:813d4f57d630 | 115 | if (to) *to = _to; |
charly | 1:813d4f57d630 | 116 | if (id) *id = _id; |
charly | 1:813d4f57d630 | 117 | if (flags) *flags = _flags; |
charly | 1:813d4f57d630 | 118 | _seenIds[_from] = _id; |
charly | 1:813d4f57d630 | 119 | return true; |
charly | 1:813d4f57d630 | 120 | } |
charly | 1:813d4f57d630 | 121 | // Else just re-ack it and wait for a new one |
charly | 0:79c6d0071c4c | 122 | } |
charly | 0:79c6d0071c4c | 123 | } |
charly | 0:79c6d0071c4c | 124 | // No message for us available |
charly | 0:79c6d0071c4c | 125 | return false; |
charly | 0:79c6d0071c4c | 126 | } |
charly | 0:79c6d0071c4c | 127 | |
charly | 1:813d4f57d630 | 128 | boolean RF22ReliableDatagram::recvfromAckTimeout(uint8_t* buf, uint8_t* len, uint16_t timeout, uint8_t* from, uint8_t* to, uint8_t* id, uint8_t* flags) { |
charly | 0:79c6d0071c4c | 129 | Timer t; |
charly | 0:79c6d0071c4c | 130 | unsigned long endtime = t.read_ms() + timeout; |
charly | 0:79c6d0071c4c | 131 | while (t.read_ms() < endtime) |
charly | 1:813d4f57d630 | 132 | if (recvfromAck(buf, len, from, to, id, flags)) |
charly | 1:813d4f57d630 | 133 | return true; |
charly | 0:79c6d0071c4c | 134 | return false; |
charly | 0:79c6d0071c4c | 135 | } |
charly | 0:79c6d0071c4c | 136 | |
charly | 1:813d4f57d630 | 137 | uint16_t RF22ReliableDatagram::retransmissions() { |
charly | 0:79c6d0071c4c | 138 | return _retransmissions; |
charly | 0:79c6d0071c4c | 139 | } |
charly | 0:79c6d0071c4c | 140 | |
charly | 1:813d4f57d630 | 141 | void RF22ReliableDatagram::acknowledge(uint8_t id, uint8_t from) { |
charly | 0:79c6d0071c4c | 142 | setHeaderId(id); |
charly | 0:79c6d0071c4c | 143 | setHeaderFlags(RF22_FLAGS_ACK); |
charly | 0:79c6d0071c4c | 144 | // We would prefer to send a zero length ACK, |
charly | 0:79c6d0071c4c | 145 | // but if an RF22 receives a 0 length message with a CRC error, it will never receive |
charly | 0:79c6d0071c4c | 146 | // a 0 length message again, until its reset, which makes everything hang :-( |
charly | 0:79c6d0071c4c | 147 | // So we send an ACK of 1 octet |
charly | 0:79c6d0071c4c | 148 | // REVISIT: should we send the RSSI for the information of the sender? |
charly | 0:79c6d0071c4c | 149 | uint8_t ack = '!'; |
charly | 1:813d4f57d630 | 150 | sendto(&ack, sizeof(ack), from); |
charly | 0:79c6d0071c4c | 151 | waitPacketSent(); |
charly | 0:79c6d0071c4c | 152 | } |
charly | 0:79c6d0071c4c | 153 |