Karl Zweimüller / Mbed 2 deprecated eth_comfort_test

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Dependencies:   TextLCD mbed

eth_comfort.cpp@0:96794c9fc5a3, 2011-03-02 (annotated)

Committer:
charly
Date:
Wed Mar 02 20:46:57 2011 +0000
Revision:
0:96794c9fc5a3
Child:
1:fc72e0bdb693
Initial pre-beta version

Who changed what in which revision?

UserRevisionLine numberNew contents of line
charly 0:96794c9fc5a3 1 /** module for receiving data from eth comfort window sensor by ELV(R) with a RFM12 transceiver module by Hope
charly 0:96794c9fc5a3 2
charly 0:96794c9fc5a3 3 Details see discussion on http://www.mikrocontroller.net/topic/172034
charly 0:96794c9fc5a3 4 Frequenz 868,3
charly 0:96794c9fc5a3 5 Modulation FSK
charly 0:96794c9fc5a3 6 Hub +/- 15kHz
charly 0:96794c9fc5a3 7 Datenrate 10kbit Manchester
charly 0:96794c9fc5a3 8
charly 0:96794c9fc5a3 9 das Protokoll ist Machester codiert
charly 0:96794c9fc5a3 10 0x7e zz ll aa aa aa cmd crc crc
charly 0:96794c9fc5a3 11
charly 0:96794c9fc5a3 12 zz ist ein fortlaufender Zaehler
charly 0:96794c9fc5a3 13 ll die Blocklaenge 10,20,30 (20 = 9 Byte, 10= 10Byte ,30= ?)
charly 0:96794c9fc5a3 14 aa 3 Byte Adresse
charly 0:96794c9fc5a3 15 cmd der Befehl
charly 0:96794c9fc5a3 16 crc 16 bit checksumme
charly 0:96794c9fc5a3 17
charly 0:96794c9fc5a3 18 die Reihenfolge der Bits im Byte ist verdreht.
charly 0:96794c9fc5a3 19
charly 0:96794c9fc5a3 20 */
charly 0:96794c9fc5a3 21
charly 0:96794c9fc5a3 22
charly 0:96794c9fc5a3 23 // WED 6.9.2009
charly 0:96794c9fc5a3 24 // extended and adapeted to mbed by Karl Zweimueller 1/2011
charly 0:96794c9fc5a3 25
charly 0:96794c9fc5a3 26
charly 0:96794c9fc5a3 27 #include "eth_comfort.h"
charly 0:96794c9fc5a3 28
charly 0:96794c9fc5a3 29
charly 0:96794c9fc5a3 30 /* orig AVR-values
charly 0:96794c9fc5a3 31 #define BIT_MAX 0x90
charly 0:96794c9fc5a3 32 #define BIT_MIN 0x10
charly 0:96794c9fc5a3 33 #define LEN_2T 0x44
charly 0:96794c9fc5a3 34 */
charly 0:96794c9fc5a3 35
charly 0:96794c9fc5a3 36 //working: 300-80-200
charly 0:96794c9fc5a3 37 // nominal values are: 208-104-208 for 9600 bits/sec
charly 0:96794c9fc5a3 38 #define BIT_MAX 300 // maximum allowed time for one or two bits high or low
charly 0:96794c9fc5a3 39 #define BIT_MIN 80 // minimum allowed time for one or two bits high or low
charly 0:96794c9fc5a3 40 #define LEN_2T 200 // time-value to differentiate one or two bit length
charly 0:96794c9fc5a3 41
charly 0:96794c9fc5a3 42
charly 0:96794c9fc5a3 43 volatile uint16_t b;
charly 0:96794c9fc5a3 44
charly 0:96794c9fc5a3 45 volatile uint8_t transmit,bit_cnt;
charly 0:96794c9fc5a3 46 volatile uint16_t buffer_cnt;
charly 0:96794c9fc5a3 47
charly 0:96794c9fc5a3 48
charly 0:96794c9fc5a3 49 volatile unsigned char old ;
charly 0:96794c9fc5a3 50 volatile uint8_t rbyte;
charly 0:96794c9fc5a3 51
charly 0:96794c9fc5a3 52 volatile uint8_t buf[1024];
charly 0:96794c9fc5a3 53 volatile uint8_t pack_ok,startbit;
charly 0:96794c9fc5a3 54 volatile uint8_t decode,bcnt,lastbit;
charly 0:96794c9fc5a3 55 volatile uint8_t state;
charly 0:96794c9fc5a3 56
charly 0:96794c9fc5a3 57 // Timer for bit-length-measurement
charly 0:96794c9fc5a3 58 Timer BitTime;
charly 0:96794c9fc5a3 59
charly 0:96794c9fc5a3 60 //-------------------------------------------------------------------------
charly 0:96794c9fc5a3 61 // calcCRC16r()
charly 0:96794c9fc5a3 62 //-------------------------------------------------------------------------
charly 0:96794c9fc5a3 63 /**
charly 0:96794c9fc5a3 64 * @brief calculate reverse CRC
charly 0:96794c9fc5a3 65 * @param c 16bit value for crc
charly 0:96794c9fc5a3 66 * @param crc old crc value
charly 0:96794c9fc5a3 67 * @param mask crc polynom
charly 0:96794c9fc5a3 68 * @return crc value
charly 0:96794c9fc5a3 69 */
charly 0:96794c9fc5a3 70 uint16_t calcCRC16r( uint16_t c,uint16_t crc, uint16_t mask) // reverser crc!!!!!!
charly 0:96794c9fc5a3 71 {
charly 0:96794c9fc5a3 72 uint8_t i;
charly 0:96794c9fc5a3 73 for(i=0;i<8;i++)
charly 0:96794c9fc5a3 74 {
charly 0:96794c9fc5a3 75 if((crc ^ c) & 1) { crc=(crc>>1)^mask; }
charly 0:96794c9fc5a3 76 else crc>>=1;
charly 0:96794c9fc5a3 77 c>>=1;
charly 0:96794c9fc5a3 78 };
charly 0:96794c9fc5a3 79 return(crc);
charly 0:96794c9fc5a3 80 }
charly 0:96794c9fc5a3 81
charly 0:96794c9fc5a3 82 // initialize eth_receiver
charly 0:96794c9fc5a3 83 void eth_init()
charly 0:96794c9fc5a3 84 {
charly 0:96794c9fc5a3 85 // start timer for bit-length-measurement
charly 0:96794c9fc5a3 86 BitTime.start();
charly 0:96794c9fc5a3 87
charly 0:96794c9fc5a3 88 }
charly 0:96794c9fc5a3 89
charly 0:96794c9fc5a3 90 //
charly 0:96794c9fc5a3 91 //
charly 0:96794c9fc5a3 92 //
charly 0:96794c9fc5a3 93
charly 0:96794c9fc5a3 94 /** ISR Interrupt routine for received data
charly 0:96794c9fc5a3 95 * triggers on every pin change high/low and low/high
charly 0:96794c9fc5a3 96 * does all the encoding of the signal including manchester decoding!
charly 0:96794c9fc5a3 97 * as the eth doesn't send a good signal, which the rfm12 could decode for himself
charly 0:96794c9fc5a3 98 * didn't test for myself - just got the code from someone else and ported to mbed!
charly 0:96794c9fc5a3 99 */
charly 0:96794c9fc5a3 100 void ISR() // pin change on rxin ->interrupt
charly 0:96794c9fc5a3 101 {
charly 0:96794c9fc5a3 102 //led2=!led2;
charly 0:96794c9fc5a3 103 b=BitTime.read_us(); // time since last change
charly 0:96794c9fc5a3 104 BitTime.reset();
charly 0:96794c9fc5a3 105
charly 0:96794c9fc5a3 106 if((b>BIT_MAX)||(b<BIT_MIN)){ // is bit time in range?
charly 0:96794c9fc5a3 107 state=0;
charly 0:96794c9fc5a3 108 }
charly 0:96794c9fc5a3 109 else{
charly 0:96794c9fc5a3 110
charly 0:96794c9fc5a3 111
charly 0:96794c9fc5a3 112 if(state==0){ // wait for first bitchange 2T
charly 0:96794c9fc5a3 113 if(b>LEN_2T)state=1;
charly 0:96794c9fc5a3 114 //if((rxin)!=0)state=0; // level should be low
charly 0:96794c9fc5a3 115 }
charly 0:96794c9fc5a3 116 else if(state<=10){ // wait for 5 fullbit without bitchange 10 shortbits
charly 0:96794c9fc5a3 117 if(b<LEN_2T)state++;
charly 0:96794c9fc5a3 118 else state=1; // bitchange found back to state 1
charly 0:96794c9fc5a3 119 }
charly 0:96794c9fc5a3 120 else if(state==11){ // now expecting bitchange (last bit in 7e is 0)
charly 0:96794c9fc5a3 121 if(b<LEN_2T){
charly 0:96794c9fc5a3 122 state=0; // no bitchange -> back to search
charly 0:96794c9fc5a3 123 };
charly 0:96794c9fc5a3 124 state=20; // now we found 7e sync finished
charly 0:96794c9fc5a3 125 rbyte=0x7e; // set shift value to 0
charly 0:96794c9fc5a3 126 bit_cnt=8; // clear bitcounter
charly 0:96794c9fc5a3 127 buffer_cnt=0; // clear buffercounter
charly 0:96794c9fc5a3 128 bcnt=0;
charly 0:96794c9fc5a3 129 lastbit=0;
charly 0:96794c9fc5a3 130
charly 0:96794c9fc5a3 131 }
charly 0:96794c9fc5a3 132 else if(state==20){
charly 0:96794c9fc5a3 133 if(b>LEN_2T){ // check for bitchange
charly 0:96794c9fc5a3 134 if(lastbit!=0){
charly 0:96794c9fc5a3 135 rbyte=(rbyte>>1); // last bit was 1 new is 0
charly 0:96794c9fc5a3 136 bcnt=0;
charly 0:96794c9fc5a3 137 lastbit=0;
charly 0:96794c9fc5a3 138 }
charly 0:96794c9fc5a3 139 else {
charly 0:96794c9fc5a3 140 rbyte=(rbyte>>1)|0x80; // last bit was 0 new is 1
charly 0:96794c9fc5a3 141 bcnt++;
charly 0:96794c9fc5a3 142 lastbit=1;
charly 0:96794c9fc5a3 143 }
charly 0:96794c9fc5a3 144 state=20; // fullbit compleate
charly 0:96794c9fc5a3 145 bit_cnt++; // increase bit counter
charly 0:96794c9fc5a3 146 }
charly 0:96794c9fc5a3 147 else{
charly 0:96794c9fc5a3 148 state=21; // bit is halfbit, wait for next halfbit
charly 0:96794c9fc5a3 149 };
charly 0:96794c9fc5a3 150 }
charly 0:96794c9fc5a3 151 else if(state==21){ // no bitchange
charly 0:96794c9fc5a3 152 if(b<LEN_2T){ // next bit must be a halfbit
charly 0:96794c9fc5a3 153 if(lastbit==0){
charly 0:96794c9fc5a3 154 rbyte=(rbyte>>1); // last bit was 0 new is 0
charly 0:96794c9fc5a3 155 lastbit=0;
charly 0:96794c9fc5a3 156 bcnt=0;
charly 0:96794c9fc5a3 157 }
charly 0:96794c9fc5a3 158 else {
charly 0:96794c9fc5a3 159 rbyte=(rbyte>>1)|0x80; // last bit was 1 new is 1
charly 0:96794c9fc5a3 160 lastbit=1;
charly 0:96794c9fc5a3 161 bcnt++;
charly 0:96794c9fc5a3 162 }
charly 0:96794c9fc5a3 163 state=20;
charly 0:96794c9fc5a3 164 bit_cnt++;
charly 0:96794c9fc5a3 165 }
charly 0:96794c9fc5a3 166 else{
charly 0:96794c9fc5a3 167 state=0; // bit is no halfbit -> Manchester violation
charly 0:96794c9fc5a3 168 // state=20;
charly 0:96794c9fc5a3 169 };
charly 0:96794c9fc5a3 170 }else if(state==22){ // after 5 bit 1 skip one bit 0
charly 0:96794c9fc5a3 171 if(b>LEN_2T){ // check for bitchange (next bit 0)
charly 0:96794c9fc5a3 172 lastbit=0;
charly 0:96794c9fc5a3 173 state=20;
charly 0:96794c9fc5a3 174 }
charly 0:96794c9fc5a3 175 else{
charly 0:96794c9fc5a3 176
charly 0:96794c9fc5a3 177 lastbit=1;
charly 0:96794c9fc5a3 178 //state=11;
charly 0:96794c9fc5a3 179 state=21;
charly 0:96794c9fc5a3 180 }
charly 0:96794c9fc5a3 181 bcnt=0;
charly 0:96794c9fc5a3 182
charly 0:96794c9fc5a3 183
charly 0:96794c9fc5a3 184 }
charly 0:96794c9fc5a3 185 if(bcnt==5)state=22;
charly 0:96794c9fc5a3 186
charly 0:96794c9fc5a3 187 if(bit_cnt>7){ // wait for 8 bits
charly 0:96794c9fc5a3 188 buf[buffer_cnt]=rbyte; // save value into buffer
charly 0:96794c9fc5a3 189 if(buffer_cnt<1020){
charly 0:96794c9fc5a3 190 buffer_cnt++;
charly 0:96794c9fc5a3 191 };
charly 0:96794c9fc5a3 192 pack_ok=1; // set receiveflag
charly 0:96794c9fc5a3 193 bit_cnt=0; // clear bitcounter
charly 0:96794c9fc5a3 194 led3= !led3; //show received byte
charly 0:96794c9fc5a3 195
charly 0:96794c9fc5a3 196 //
charly 0:96794c9fc5a3 197 };
charly 0:96794c9fc5a3 198 };
charly 0:96794c9fc5a3 199
charly 0:96794c9fc5a3 200 }
charly 0:96794c9fc5a3 201
charly 0:96794c9fc5a3 202
charly 0:96794c9fc5a3 203
charly 0:96794c9fc5a3 204