Truyn tn hiu vi module radio frequence 433Mhz

Truyn tn hiu vi module radio frequence 433MhzNTP_PROgi voTh nm, 14 Thng 8, 2014 - 19:30Xin cho cc bn, bi vit hm nay ca mnh s gii thiu v cch truyn d liu khng dy bng modules RF (radio frequence) 433Mhz.PHN CNGBoard Arduino x2 ( mnh s dngArduino UNO R3v Arduino Leonardo).Module RF 433 Mhz ( gm 1transmitter modulev 1receiver module) hoc 315MHz.Breadboardx2.LED xanh, vng, .in tr (220 - 560 m)pin 9V x2.Dy dn.GII THIUMODULE RF 433Mhz:y l 1 module gi r, dng sng radio truyn tn hiu gia b pht (transmitter module) v b thu (receiver module).Mo: tng hiu qu v khong cch khi s dng module RF, cc bn c th ch 2 ci ngten bng dy ng cun thnh l xo ri gn vo ngten ca transmitter v receiver.nh module ca mnh:

-Transmitter module: l ci module nh hn , gm 3 chn: t tri qua phi: DATA (hoc ATAD), VCC, GND.Transmitter moduleArduino

DATAdigital Pin

VCC5V

GNDGND

-Receiver module: l ci to hn, gm 4 chn: t tri qua phi: GND, DATA, DATA, VCC. (chng ta ch dng 1 trong 2 chn DATA ny)Transmitter moduleArduino

DATAdigital Pin

VCC5V

GNDGND

hiu r hn v sng radio, cc bn c th tham kho ti bi vit sau:http://arduino.vn/bai-viet/277-song-vo-tuyen-la-gi-va-nhung-suc-manh-cua-no-khi-ket-hop-voi-arduinoChng ta s tm hiu cch truyn d liu vi RF module ngay by gi.LP MCH

Trong Transmitter module, mnh s dng pin 8 pht tn hiu.Trong Receiver module, mnh cng s dng pin 8 nhn tn hiu.LP TRNH s dng RF module 1 cch d dng hn, chng ta s download th vin VirtualWire ti link sau:http://www.airspayce.com/mikem/arduino/VirtualWire/VirtualWire-1.27.zipSau , cc bn m Arduino IDE, chn Sketch/ Import Library.../ Add Library... v chn vo file .zip va ti v ci t th vin. Transmitter module, mnh s nhn d liu t cng Serial, sau gi sang Receiver module.Transmitter:#include // khai bo th vin VirtualWirevoid setup(){ Serial.begin(9600);// giao tip Serial vi baudrate 9600 Serial.println("Ready........."); vw_set_ptt_inverted(true);// yu cu cho RF link modules vw_setup(1024);// ci t tc truyn tn hiu vw_set_tx_pin(8);// ci t chn digital pht tn hiu}void loop(){ char text[20] = "";// khai bo string dng array byte i = 0; while (Serial.available() == 0) { // nothing } while (Serial.available() > 0) { char ch = Serial.read(); text[i] = ch; i++; delay(5); } Serial.print("sent: "); Serial.println(text); vw_send((byte *)text, sizeof(text));// gi tn hiu i vw_wait_tx(); delay(100);}Receiver:#include // khai bo th vin VirtualWirebyte msg[VW_MAX_MESSAGE_LEN];// bin lu d liu nhn cbyte msgLen = VW_MAX_MESSAGE_LEN;void setup(){ Serial.begin(9600); Serial.println("READY.........."); vw_setup(1024); // ci t tc truyn tn hiu vw_set_rx_pin(8);// ci t chn digital nhn tn hiu vw_rx_start();// bt u nhn tn hiu}void loop(){ if (vw_get_message(msg, &msgLen)) // nu c tn hiu c truyn n { Serial.print("got: "); for (int i = 0; i < msgLen; i++) { Serial.write(msg[i]);// in k t ra mn hnh } Serial.println(); }}Ch : Khi upload 2 on code trn ln 2 boards Arduino, cc bn cn bt 2 ca s Arduino IDE ring bit (tc l phi 2 ln double click vo biu tng Arduino IDE), v mi board s c 1 cng COM ring, nn cc bn ch vo Tools / Serial Port... chn ng cng COM cho board.

Sau khi upload code ln 2 boards Arduino, cc bn m 2 ca s Serial ca 2 boards, ri nhp vi k t vo ca s Serial ca Transmitter, KQ s tng t th ny:

GII THCH- Transmitter s nhn d liu t Bn phm qua cng Serial, sau Transmitter s gi d liu ny n Receiver bng sng radio, khi Receiver nhn c tn hiu, n s gii m v in ra ca s Serial.- Theo mc nh, th vin VirtualWire chn pin 12 pht tn hiu, pin 11 nhn tn hiu. Cc bn c th ty chn 1 chn digital bt k gi v nhn tn hiu vi dng lnh:vw_set_tx_pin(pin) i vi transmitter vvw_set_rx_pin(pin) i vi Receiver.- Cc keywords:vw_set_ptt_inverted(true): cn phi c i vi RF link modules, c th khng cn thit i vi cc loi modules khc.vw_setup(speed): thit lp tc truyn d liu gia Transmitter v Receiver, n v: bits/s. Ch : tc ca Transmitter v Receiver phi bng nhau.vw_set_tx_pin(pin): thit lp chn pht tn hiu.vw_set_rx_pin(pin): thit lp chn nhn tn hiu.vw_rx_start(): bt u nhn tn hiu.vw_send((byte *)data, sizeof(data)): hm gi tn hiu i, gm 2 tham s l:(byte *)data:bin con tr (byte *)data, trong : data l bin cha d liu cn c truyn i, bin data cn c khai bo l bin mng. C th v d trn l bin text[20].sizeof(data):kch thc ca d liu c truyn i, tnh theo byte. Ch : nu bn khai bo string kiu con tr, VD: const char *text = "hello"; lc ny bn s phi dng strlen(text) thay v sizeof(text).vw_get_message(msg, &msgLen): hm nhn tn hiu, s tr v gi trtruekhi c tn hiu c gi ti, gm 2 tham s l:msg:bin con tr msg, trong : msg l bin cha d liu va nhn c, bin msg cn c khai bo l bin mng. v d trn l bin msg[VW_MAX_MASSAGE_LEN].&msgLen:a ch ca bin msgLen, bin msgLen ch kch thc ca d liu nhn c.vw_wait_tx(): i trc khi truyn tn hiu tip theo.VW_MAX_MASSAGE_LEN: th vin VirtualWire define sn kch thc ti a ca d liu l 30 bytes.By gi, mnh s s dng sng radio iu khin cc thit b in t.LP MCHTransmitter

Receiver

LP TRNHMnh s gi lnh t Transmitter n Receiver iu khin bt/tt cc LED.Lnh s c c php: "number STATE"VD: 1 ON ===> led sng, 2 OFF ===> led xanh tt, 3 ON ===> led vng sng, A ON ===> bt tt c led, A OFF ===> tt tt c led,...Transmitter (tng t nh v d trn):#include void setup(){ Serial.begin(9600); Serial.println("Ready........."); vw_set_ptt_inverted(true); vw_setup(1024); vw_set_tx_pin(8);}void loop(){ char text[20] = ""; byte i = 0; while (Serial.available() == 0) { // nothing } while (Serial.available() > 0) { char ch = Serial.read(); text[i] = ch; i++; delay(5); } Serial.print("sent: "); Serial.println(text); vw_send((byte *)text, sizeof(text)); vw_wait_tx(); delay(100); }Receiver:#include byte msg[VW_MAX_MESSAGE_LEN];byte msgLen = VW_MAX_MESSAGE_LEN;const int RED = 7; // led const int GREEN = 6; // led xanhconst int YELLOW = 5; // led vngString text = ""; // bin String lu d liu void setup(){ Serial.begin(9600); Serial.println("READY.........."); pinMode(RED, OUTPUT); pinMode(GREEN, OUTPUT); pinMode(YELLOW, OUTPUT); vw_setup(1024); vw_set_rx_pin(8); vw_rx_start();}/* select */void select(byte number, byte name){

// lnh c dng "number STATE", VD: 1 ON, 2 OFF, 3 ON... // i bt u ti 2 b qua "number" v "khoang trang" // bt u kim tra c "STATE" lun for (int i = 2; i < msgLen; i++)

{ text += char(msg[i]); } Serial.print("got: "); // in kt qu ra ca s Serial Serial.print(number); Serial.print("-"); Serial.println(text); /* nu "STATE" = ON ==> bt, nu "STATE" = OFF ==> tt*/ if (text == "ON") { digitalWrite(name, 1); } else if (text == "OFF") { digitalWrite(name, 0); }}/* select All*/void selectAll(){ for (int i = 2; i < msgLen; i++) { text += char(msg[i]); } Serial.print("got: ALL"); Serial.print("-"); Serial.println(text); if (text == "ON") { digitalWrite(RED, 1); digitalWrite(GREEN, 1); digitalWrite(YELLOW, 1); } else if (text == "OFF") { digitalWrite(RED, 0); digitalWrite(GREEN, 0); digitalWrite(YELLOW, 0); }}void loop(){ if (vw_get_message(msg, &msgLen)) { if (msg[0] == '1') { select(1, RED); } else if (msg[0] == '2') { select(2, GREEN); } else if (msg[0] == '3') { select(3, YELLOW);

} else if (msg[0] == 'A') { selectAll(); } } text = ""; // reset bin text}Sau khi upload thnh cng v test th, chng ta s c ca s Serial nh sau:

y l 1 s hnh nh v project ca mnh

LI KTKt hp vi rle, cc bn hon ton c th iu khin t xa cc thit b in trong gia nh thng qua my vi tnh.Chc cc bn thnh cng!Mi thc mc v sai st cc bn c comment nh!^^11066 lt xem