Hello,
I'm thinking about upgrading this board to include pinout for LIS3DH breakout board, like this one :
https://www.aliexpress.com/item/LIS3DH-Three-Converters-Motion-Accelerometer-Triaxial-Acceleration-Temperature-Sensor-Module-Development-Board-Replace-ADXL345/32840326778.html
and ditch the ADXL shield as it's not a good solution, it has either the ADXL345 which uses too much power, or the ADXL362 which is ultra low power but lacks advanced functionality like tap/double tap detection.
I would like to have feedback of users on this (do it sound useful ?), and also know if anyone uses the SMD footprints on the board, for leds and for reserve capacitors, as it could be a cleaner board without those footprints.
I would make the following changes :
put footprint for LIS3DH accelerometer along the "NModule connector" as it has too many pins to put elsewhere
keep only one I2C footprint on the side, for "GY-49" MAX44009 light sensor breakout board: https://www.aliexpress.com/item/GY-49-MAX44009-Ambient-Light-Sensor-Module-for-Arduino-with-4P-Pin-Header-Module/32828654450.html
temperature/humidity would be via the existing "SMD" footprint, it's not through hole but very easy to solder as it's 2.54mm pad spacing
remove SMD footprints for LED, add footprint for through hole reserve capacitor, keep SMD footprints for reserve capacitors only if I have space for them
shield would be a bit extended to go over the 2 M2 holes in the "power" part of the NModule, so it could be fitted with spacers and nylon screws and have stable/reliable mechanical connection between NModule and Shield. Basically this would be the footprint of the shield :
So in the end it would make one shield to have Temperature/Humidity/Light/Acceleration or Temperature/Humidity/Light/Door.
@yoshi824 Most of us have been where you are now!
I suggest that you try to see the patterns in the code that you have working and try to make the SHT30 work from what you learn.
If it does not work as you want then post here the full code you have and what it is/isn't doing and you should get some help.
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;
}
To provide a large enough pulse to drive the ceramic transducer , you need a lot of energy, so they pump up the 5v with an inductor/transformer to provide a high voltage pulse. This is 60v or more…
The more Energy you produce the farther the pulse will travel….
Everything thing else on the board run at 3.3 to 5V.
Add a large Capacitor of 100 µF are so between the 5v and ground on the device, this may clean up your problem.. Some CPU modules just can’t supply enough current quick enough that’s needed when the pulse is triggered.
These are very inexpensive device, we’re luck to see them work at 1/2 the spec range.
