I solved following serial port related problems in ubuntu 18.04 as follows:
Problem 1 : Cannot open /dev/ttyACM0: Permission denied
Solution : Grant permissions to read/write to the serial port with this terminal command ---> sudo chmod a+rw /dev/ttyACM0
Here replace tty port with your respective ubuntu port.
Problem 2 : Failed to open /dev/ttyACM0 (...
Making your board definition work
What I did was slightly different from their directions, but:
Close any instances of the IDE you have running.
Create the directories along this path:
Where <sketchbook> refers to to where your IDE is saving sketches by default.
Place the following slightly ...
That's not how you compare C strings.
When you write
if (topic == "/home/bedroom/light1")
you're comparing whether the character pointer topic is the same value as the address of the string "/home/bedroom/light1", which of course it is not in this case.
To compare C strings, use the strcmp() function, which returns 0 if they're identical....
The "high density" connectors expose every pin of the MCU. The pins around the edge of the board duplicate just the immediately useful ones.
Every pin that is on the edge of the board is also on the high density connectors somewhere.
Why have the pin on both connectors? Simple: if you want to use it in a breadboard or with jumper wires then you ...
Your problem is that you don't know what ADC value maps to the maximum RPM. If you did you wouldn't need to know the RPM.
What you have here is a "feedback loop", and what you need is some method of using the detected RPM to control the speed of the motor.
You need to decouple the potentiometer from the analogWrite completely - the potentiometer ...
We work with Proculus displays, and we are a distributor of this display here in Brazil (Victor Vision). The display is great, very professional. Used in medical equipments, and cheaper than Nextion.
They are starting now in the web and selling in Alibaba.
As @timemage explains in a comment, you cannot pass a capturing lambda
to a function that expects a plain pointer to function. There is,
however, a way out of this: the Ticker class provides an overload of
the attach() method that allows you to provide a parameter of any type
to tour callback:
void attach(float seconds, void (*...