Good Morning / Afternoon / Evening peeps! I was wondering if I could get some (more) help. I have this piece of code that works as the master unit for a garage door opener. What happens is there is are a master and slave units that are connected via bluetooth (HC-05.) The master is in the garage and the slave is in the house. When I press a button on the slave, a relay at the master unit is closed for as long as the button is pressed. As it stands everything works great. I recently redesigned the project to add another relay so when the button is pressed at the slave unit, the second relay at the master unit is closed for a pre-determined amount of time (turning a light on) and then opening again. I thought about using millis but I have no clue how to implement that, or if there's a better way. I don't think I need to have this controlled by the button at the slave, I thought that maybe when the reed switch opens or closes that it could trigger the second relay. Anyhoo below is my code and parts list. Fire any questions at me, I tried to be as thorough as possible. Thanks in advance. Relay Arduino Nano HC-05 Bluetooth Module TP4056 Charging Module Buck Converter Step-Up Converter 2N2222 Transistors LED's Diodes Capacitors Resistors [GARMASFRO] [GARMASBAC] MASTER CODE #include #include #define redLed 6 #define greenLed 9 #define blueLed 10 #define GarSwitch 4 #define relay1 5 #define relay2 11 int garageState = 0; int lastGarageState = 0; char ch; String HC05_Awake = "ON"; SoftwareSerial mySerial(7, 8); // Rx | Tx void setup() { Timer1.initialize(40000000); Timer1.attachInterrupt(KeepAlive); Serial.begin(115200); mySerial.begin(38400); pinMode(GarSwitch, INPUT_PULLUP); lastGarageState = digitalRead(GarSwitch); pinMode(relay, OUTPUT); pinMode(redLed, OUTPUT); pinMode(greenLed, OUTPUT); pinMode(blueLed, OUTPUT); digitalWrite(redLed, LOW); digitalWrite(greenLed, LOW); digitalWrite(blueLed, LOW); digitalWrite(relay1, HIGH); digitalWrite(relay2, HIGH); digitalWrite(greenLed, HIGH); } int counter; void loop() { // Sending // read input once garageState = digitalRead(GarSwitch); // LOW = pressed if (garageState != lastGarageState) { if (garageState == LOW) { // switch got pressed Serial.print(counter); counter++; Serial.println(" Print an 'a'"); mySerial.print('a'); digitalWrite(blueLed, LOW); digitalWrite(redLed, LOW); digitalWrite(greenLed, HIGH); } else { // switch got released Serial.print(counter); counter++; Serial.println(" Print a 'c'"); mySerial.print('c'); digitalWrite(blueLed, LOW); digitalWrite(greenLed, LOW); digitalWrite(redLed, HIGH); } } if (mySerial.available()) { char ch = mySerial.read(); Serial.write(ch); if (ch == 'b') { Serial.print(counter); counter++; Serial.println(" Print a 'b'"); mySerial.print('b'); digitalWrite(blueLed, LOW); digitalWrite(redLed, HIGH); digitalWrite(greenLed, LOW); digitalWrite(relay1, LOW); delay(1000); } else { Serial.print(counter); counter++; Serial.println(" Print a 'd'"); mySerial.print('d'); digitalWrite(blueLed, LOW); digitalWrite(redLed, LOW); digitalWrite(greenLed, HIGH); digitalWrite(relay1, HIGH); } } lastGarageState = garageState; delay(20); // poor man's debouncing } void KeepAlive() { if (HC05_Awake = "ON") { mySerial.print('m'); Serial.print('m'); } } SLAVE CODE // slave # include SoftwareSerial mySerial(7, 8); // Rx | Tx # define redLed 5 # define greenLed 6 # define blueLed 10 # define Button 3 # define pwrLed 9 char ch; int buttonState = 0; int lastButtonState = 0; int counter; void setup() { Serial.begin(115200); mySerial.begin(38400); pinMode(pwrLed, OUTPUT); pinMode(redLed, OUTPUT); pinMode(greenLed, OUTPUT); pinMode(blueLed, OUTPUT); pinMode(Button, INPUT_PULLUP); analogWrite(pwrLed, 3); } void loop() { // read input once buttonState = digitalRead(Button); // LOW = pressed if (buttonState != lastButtonState) { mySerial.print('a'); if (buttonState == LOW) { // switch got pressed Serial.print(counter); counter++; Serial.println(" Print a 'b'"); mySerial.print('b'); digitalWrite(blueLed, HIGH); digitalWrite(redLed, LOW); digitalWrite(greenLed, LOW); } else { // switch got released Serial.print(counter); counter++; Serial.print(" Print a 'd'"); mySerial.print('d'); digitalWrite(blueLed, LOW); digitalWrite(greenLed, LOW); digitalWrite(redLed, HIGH); } } //... // Receiving if (mySerial.available()) { char ch = mySerial.read(); Serial.write(ch); if (ch == 'a') { Serial.print(counter); counter++; Serial.println(" Print an 'a'"); analogWrite(redLed, 0); analogWrite(greenLed, 50); analogWrite(blueLed, 0); } else if (ch == 'c') { Serial.print(counter); counter++; Serial.println(" Print a 'c'"); mySerial.print('c'); analogWrite(redLed, 255); analogWrite(greenLed, 0); analogWrite(blueLed, 0); } } lastButtonState = buttonState; delay(20); // poor man's debouncing }

unsigned long currentMillis; // unsigned long because you don't want the clock to run out unsigned long previousMillis; // store last time we checked millis() free running clock const int delayTime = 1000; // const because we always want the delay this long void setup(){ // your stuff } void loop(){ // your other stuff // start our named (currentMillis), built in, free running, no blocking timer (millis() function) currentMillis = millis(); if (currentMillis - previousMillis > delayTime) { previousMillis = currentMillis; // like pressing 'lap' on a stopwatch // do the thing for the timed interval } // maybe some of your other stuff } If you want a delay time of more than 30 seconds, change the delayTime variable to const long because on an Uno R3 anyway, int rolls over (into negative numbers) after 32,767.

I get that, but how do I implement it without affecting the other parts of the code? Thanks for the response by the way.

Cool thanks. Gonna give it a try. I'll keep you posted.

Here's something to play around with to help understand what's going on. I had a really hard mental barrier to understanding this millis timer concept. This is the most boring game in the world. All that happens is, you watch the serial monitor and it increments the game level every 5 seconds, no user interaction required, but also no external hardware required so there's that at least. Take 'er for a rip if you like, just don't give me a negative review on Steam Games, please :wink: /* April 03, 2024 Brandon Ruys State/Mode Machine - timed leveled events Working as intended */ byte level; // you could have 0 - 255 levels if you wanted. unsigned long currentTime; unsigned long lastTimeAround; void setup() { Serial.begin(115200); Serial.println(F("millisTimerLeveledEvents")); delay(500); Serial.println(); level = 0; // start at level 0 currentTime = 0; lastTimeAround = 0; } void loop() { // start free running timer currentTime = millis(); // set conditional statement whose condition is to check clock and report every 5 seconds if (currentTime - lastTimeAround > 5000) { switch (level) { case 0: zero(); break; case 1: one(); break; case 2: two(); break; case 3: three(); break; case 4: four(); break; } // synch the time marker to the free running clock lastTimeAround = currentTime; } } void zero() { Serial.print("Game runtime: "); Serial.println("5 sec"); level += 1; // increment level by one, exit to level (case) 1 } void one() { Serial.print("Game runtime: "); Serial.println("10 sec"); level += 1; // exit to level 2 } void two() { Serial.print("Game runtime: "); Serial.println("15 sec"); level += 1; } void three() { Serial.print("Game runtime: "); Serial.println("20 sec"); level += 1; } void four() { Serial.print("Game runtime: "); Serial.print("25 sec"); Serial.println(" - Resetting to Level 0"); level = 0; // reset game to level 0 }

Lol, I would never do such a thing to someone who is trying to help me. I truly appreciate your help.

there´s an excelent tutorial in this site showing how to handle many things (n buttons) without blocking. read it and it will clarify many points...

Thanks again but I think I'm going to restart this and go in a different direction. I've decided to make the relay close on motion detection (Using This Motion Sensor), so I'll have to figure out how to code it and then I'm sure I'll be back here to ask for more help lol. I already have the sensors, now I just need to mock it up then order the new boards.

[image] Using millis() for timing. A beginners guide Tutorials Part 1 It is not usually long before new Arduino users discover that although the delay() function is easy to use it has side effects, the main one of which is that its stops all activity on the Arduino until the delay is finished (not quite true, I know, but that is usually how the problem presents itself). When this occurs the new user is usually directed to the BlinkWithoutDelay example sketch (BWoD) and/or the excellent thread entitled Several things at the same time. Several things at the… [image] Demonstration code for several things at the same time General Guidance NOTE for newcomers. The demo is entirely contained in this Post and Reply #1. There is no need to read further unless you are interested. ...added 25Sep2014 There have been a few occasions recently where newcomers seemed to have difficulty applying the "blink without delay" and "state" concepts to a sketch that is intended to manage a number of concurrent actions. Its very time consuming to respond with suitable code examples - particularly as every case is a little different. I have prepared… check these two on the matter of "several things at the same time"

[image] musicman608: Thanks again but I think I'm going to restart this and go in a different direction Could always just rig a servo to press the existing interior garage door button. I mean, it works, I've done it...

look this over # include const int PinLed [] = { 6, 9, 10 }; const int PinRly [] = { 5, 11 }; const int PinGarSw = 4; const int Nled = sizeof(PinLed)/sizeof(int); const int Nrly = sizeof(PinRly)/sizeof(int); enum { Red, Green, Blue }; enum { Off = HIGH, On = LOW }; int swState; bool tmr; const unsigned long MsecPeriod = 1000; unsigned long msec0; unsigned long msec; String HC05_Awake = "ON"; SoftwareSerial mySerial (7, 8); // Rx | Tx // ----------------------------------------------------------------------------- void setLeds ( int redLed, int grnLed, int bluLed ) { digitalWrite (PinLed [Red], redLed); digitalWrite (PinLed [Green], grnLed); digitalWrite (PinLed [Blue], bluLed); } // ----------------------------------------------------------------------------- void actA () { Serial.println (__func__); mySerial.println ('a'); setLeds (On, On, Off); digitalWrite (PinRly [0], On); tmr = true; msec0 = msec; } void actB () { Serial.println (__func__); mySerial.println ('b'); setLeds (Off, Off, On); digitalWrite (PinRly [0], Off); } // ----------------------------------------------------------------------------- void loop () { msec = millis (); if (tmr && msec - msec0 >= MsecPeriod) { tmr = false; actB (); } // monitor garage switch int sw = digitalRead (PinGarSw); if (swState != sw) { swState = sw; delay (20); // debounce if (swState == LOW) // pressed actA (); } // monitor serial input if (mySerial.available()) { char ch = mySerial.read (); if ('b' == ch) actB (); else if ('a' == ch) actA (); } } // ----------------------------------------------------------------------------- void KeepAlive () { if (HC05_Awake == "ON") { mySerial.print ('m'); Serial.print ('m'); } } // ----------------------------------------------------------------------------- void setup () { Serial.begin (115200); mySerial.begin (38400); pinMode (PinGarSw, INPUT_PULLUP); swState = digitalRead (PinGarSw); for (unsigned n = 0; n < Nrly; n++) { pinMode (PinRly [n], OUTPUT); digitalWrite (PinRly [n], Off); } for (unsigned n = 0; n < Nled; n++) pinMode (PinLed [n], OUTPUT); setLeds (Off, Off, Off); }

NON-BLOCKING CODE to turn a light on

Projects Programming

osval November 22, 2024, 7:52pm 10

check these two on the matter of "several things at the same time"

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NON-BLOCKING CODE to turn a light on

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