Hardware

I have success! (oops, that's suppose to be Timer1) I only sample for 1/60 of a second. What I did was to back up all the timer registered I used and then resorted them after I was done sampling. (As opposed to initializing the registers in setup and then starting the timer when needed.) Now I have a Nano sampling the data and sending it to a MySensors Gateway on an RPi3B+ which then sends it to an MQTT broker runing on an old laptop. Also running on the laptop is Home Assistant running inside of VirtualBox. If MySensors does use Timer1, it appears that restoring the registers allows it to be shared. //------------------------------------------------------ISR ISR(TIMER1_OVF_vect){ // interrupt service routine for overflow TCNT1 = TimerPreloadValue; // must be first line! starts the timer counting again digitalWrite(TRIGGER_START_SAMPLE_PIN,HIGH); samplesVolts[--sample]=analogRead(VOLTS_IN_PIN); // decrement before capturing samplesCurrent[sample]=analogRead(CURRENT_IN_PIN); digitalWrite(TRIGGER_START_SAMPLE_PIN,LOW); if (!sample){ // count down to zero digitalWrite(TRIGGER_START_SAMPLE_PERIOD_PIN,LOW); // indicate that sampling is complete samplingEnd = micros(); TCCR1B &= 248; // turns off timer } } //------------------------------------------------------sampleOneCycle void sampleOneCycle(){ // back up timer registers uint8_t TCNT1_b = TCNT1; uint8_t TCCR1B_b = TCCR1B; uint8_t TCCR1A_b = TCCR1A; uint8_t TIMSK1_b = TIMSK1; // configure timer which starts the sampling noInterrupts(); // disable all interrupts TCCR1A = 0; TCCR1B = 0; TCNT1 = TimerPreloadValue; // preload timer //TCCR1B |= (1 << CS10)|(1 << CS12); // 1024 prescaler TCCR1B &= 248; // turns off timer? TIMSK1 |= (1 << TOIE1); // enable timer overflow interrupt ISR // demark sampling sample = NUMBER_OF_SAMPLES; // count down to zero digitalWrite(TRIGGER_START_SAMPLE_PERIOD_PIN,HIGH); samplingStart = micros(); TCNT1 = 65535; // first trigger right away! TCCR1B |= 1; // turns on timer interrupts(); // enable all interrupts // wait for sampling to be complete while(digitalRead(TRIGGER_START_SAMPLE_PERIOD_PIN)){}; samplingEnd = micros(); // restore timer registers TCNT1 = TCNT1_b; TCCR1B = TCCR1B_b; TCCR1A = TCCR1A_b; TIMSK1 = TIMSK1_b; }

I bought the Every because it implied it was backward compatible with the nano. No, it's not, as we found out. Be that as it may, any word on a getting the Every working with mySensors?

@eiten I haven't yet made any progress on finding a good VOC sensor, but along the way I did find out something interesting regarding CO2: namely, if you sleep with your bedroom door closed at night, then the odds are good that the CO2 levels rise to surprisingly high and unhealthy levels. The better CO2 sensors are factory calibrated and never again need recalibration for the life of the sensor (usually around 10 years or so), because they are used in HVAC systems to control fresh air intake to guarantee indoor air quality. As a for instance, here is one such CO2 sensor: https://www.digikey.com/en/products/detail/senseair/006-0-0008/15790694 At around $50 for just the sensor element itself, it's not exactly cheap, but then again, I'd say it's worth it, because who wants to be burdened by remembering to calibrate their CO2 sensors? Ideally, I'd like to find a sensitive VOC sensor that also will never require calibration. Nearly all, and maybe all, of the off-the-shelf IAQ montoring stuff that you might buy for, say, $300 or less seems to require periodic calibration. For that reason, this might be one of those occasions where build is rather than buy.

@Tmaster Never assume the original PCB was just a circuit of components, the PCB can incorporate RF shields and antenna radio ground planes...

Supposedly PIR doesn't work through glass (e.g. if looking for motion through a window), whereas I presume a microwave sensor might still work.

I am new in this forum and I have a question regarding mysensors and iobroker. I did not work with mysensors up to now. Since some weeks I use iobroker installed on a raspberrypi. Now I want to integrate my 433 Mhz doorbell in iobroker. I know, that there is an adapter for mysensors in iobroker. My question is: Is it possible to get a notification in iobroker if someone is pressing the button on my doorbell? As I understood, I have to connect the receiver to an arduino nano and connect the arduino to my rasberrypi on which iobroker is running.

Great! I'm glad it works and thank you very much for reporting back!

https://github.com/sandeepmistry/arduino-nRF5 Install this and find libraries for whatever sensors you have on that board. @basaksts said in nRF5 Multi Sensor Board (12-14€): Also I need an bootloader No, you really don't. You need ST-Link, or J-Link SWD programmer/debugger. Connect it to SWDIO, SWCLK, 3.3V and GND and program it using Arduino IDE.

It's an awfully convoluted way of doing things but suspect your error lies in misunderstanding calculations mixing ints and floats and something screwy with your resistor bridge - It is always worth checking the bridge with a multimeter and raw voltage to verify the expectation. If you have 3v at the top of your voltage divider, you should be getting 0.9593v applied on the ADC pin which will be read as 892 against the 1.1v internal reference. The easiest way I found was to define a multiplier needed to derive the raw voltage, in this case (((R1+R2)x1.1)/R2) - For your resistor arrangement the max you can read is 3.4404v before exceeding the 1.1v internal reference. To reverse the ADC reading of 892 to raw voltage is (892x3.4404)/1023 = 2.9984 v. Perhaps this is a simpler way to do it float MULTIPLIER= (((1000+470)*1.1)/470);//Resistor bridge values in k and Vref int sensorValue = analogRead(BATTERY_SENSE_PIN); float batteryV = (sensorValue * MULTIPLIER)/1023.0; //Note the trailing decimal point on the 1023 for calculations involving floats

@__isded__ from what is explained in this page it seems it is based on the Semtech SX1278 : https://www.makerfabs.com/sx1278-lora-module-433m-10km-ra-02.html

Hello Jeelet, Thank you for the encouragements. Your advice to save (protect) the Oled screen is also welcome, thank you. My code expects it, the text is mini and moves every 3 seconds. Press a key and the menu returns. [image: 1674245032109-mysensors2d.png] Cordially.

I just tested 2 led types with no flicker on my attiny circuit. It is funny, the expensive leds like from philips: Dimmable 3.8W Warm White have a flickering behavior . A cheap one available in Action from LSC 6.3W, Dim to Warm and 460 Lumen has no flickering behavior. Another one from Osram Par 1650: 5.5W Dimmable Warm White, 350 Lumen also has no flickering. The philips has the best Energy savings though : 4kWh compared to 7kWh for the LSC one. Is there a relation between energy savings and dim quality ?

@mfalkvidd I finally got it to work. Look at my post on the Home Assistant forum. There is an amazing thing that someone in the MySensors world did that makes RPi I/O very easy! Just like the Arduino, one uses the code: pinMode(MphysicalPin, OUTPUT); I couldn't believe my eyes when I saw that. And then got double flabbergasted when I discovered that pin is the physical pin of the RPi! No mapping of GPIOi to the pins. Whew! So the I/O was easier than both of us could have imagined! @mfalkvidd if you know who did this, send them praise and thanks. OSD

thanks for sharing!

I would think that it's the ambient air temperature that affects how much condensate you collect, together with how much fuel was burned. After the initial warm-up that gets you to steady state, wouldn't the efficiency be constant? If the acidity is a problem, you can run the condensate over a bed of acid neutralizing rocks before it goes down your main drain. It's a thing.

I would like to step up 3.3V from my power supply with the help of a dc-dc-boost converter to 5V and then I want to draw 500mA by placing a 10 Ohm resistor between the output-pin of the boost-converter and ground.

@skywatch great, thanks a lot for your suggestion. A bit of research on the internet educated me about these diodes :D looks like they already exist on the board that carries the relay. However, i deeply thank you for the info. This forum and internet in general is such a powerful tool :+1: @ejlane your concern is fully justified :+1: i also come from an engineering background and i like to think "worse case scenario". The more one look the more one find that the very vast majority or microwave ovens work the same way : there are 3 industrial switches built in the door lock. 2 of them are cabled on the "power side", one is for signaling ("software side"). So we are pretty safe on that matter. But you are so right about safety. Magnetron do emitt dangerous waves and capacitors and stuff packed in the oven can be deadly because of high voltage. Thanks both for suggestions. I will come back with updated sketches and beg for advice once more ;)