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;
}
@mr_red
I have a zipped snapshot of all the 3d step/wrl models that I used to build my projects so far. It was quite some work to gather them all and align with the footprints using the kicad stepup tools. It's not complete - still needs some more work:simple_smile: but it should help you or anyone else to get started into MCAD integration using FreeCAD and kicad stepup tools. Maybe it's not very easy to start when using free tools but hey they are "FREE" so we cannot ask for more. But the nice thing is that once you get used it will be really easy to do your stuff and to go forward. Oh and FreeCAD can be so powerful after you learn it - I was really amazed what you can do with it(it has it's quirks and downsides but once you master it - oh, well...).
There's also: https://www.onshape.com/ - pretty powerful this one too and it has more advanced features than FreeCAD but the downside is that it's a cloud based solution: it's free for public documents but you never know when they will go to paid accounts only so yeah...I don't really like the idea to depend on something that it's hosted and the application is not on my PC along with the documents that I create with it. Cloud solutions have their flexibility but you're locked and you depend entirely on that hosted service.
Ok, enough talking...I uploaded the zip file here: http://www.mediafire.com/file/kzh1l9uo40cpj1u/kicad_stepup_packages.zip
@Yveaux Thanks for your response. I guess that's it. I have to burn a bootloader first :-). I have a USBasp Programmer for that. Can you point me to a wiring diagram that shows how to connect the programmer to the circuit board?
Advantage of this sensor is fast and easy installing by the non qualified personal. The sensor is designed for large agriculture facility with many greenhouses where is needed to be controlled temperature and humidity, the atmospheric pressure is for control the motor of air inlet and outlet. With help of the sensor installed outside the greenhouse provide information about positive/negative pressure inside the greenhouse.
Finlay the software read accurate temp/humid value of the Si7021, and only atmospheric pressure of BMP180, the temperature sensor inside the BMP180 is used only by the sensor itself to provide accurate atmospheric pressure measurements.
The sensor can be used also for home automation, and drone applications where is needed correction of the UAV barometric sensor compared to the ground barometric sensor, also humidity measurement can help the pilot to calculate more accurate flying time.
