analogWrite on Maxi

[koderjan]

Hello,

I’m experiencing a strange phenomenon with two Controllino Maxi devices (One regular Maxi and one Maxi automation).

The devices are connected to a 24V power supply and I’m using analogWrite to set voltage at a certain level, but I can only set it to 0V or to 4.8V.

I created a very basic script with a for loop which increases the value for analogWrite from 0 to 250, and back to 0 again.

I notice that when the for loop (while counting up) reaches a value of approx.. 150 the pin goes from 0 to 4.8V

and when counting down from a value of 250 the voltage drops to 0V when approx. 150 is reached.

If this is helpful for you, I can send you a video which shows this behavior through wetransfer or whataspp (30 sec, 113 Mb).

My expectation is to be able to set the voltage anywhere between 0V and 24V.

Is this a fabrication error or am I missing something?

This is the code I’m using to test:

#include

#define DbgPrintLn(X)

Serial.println (X);

//-- Declaration of some global variables

int GPinNo = CONTROLLINO_A1;

int GMaxValue = 250;

int GDbgFreq = 1;

int GDelayStep = 50; //ms

//-- Setup section

void setup() {

//-- Start Serial

Serial.begin(115200); // start serial for output

while (!Serial) {

; // wait for serial port to connect. Needed for Leonardo only

}

delay(1500);

Serial.println(F("Serial started"));

pinMode(GPinNo, OUTPUT );

delay(10000);

}

//-- Main routine

int lLoop = 0;

int lValue = 0;

void loop() {

lLoop++;

DbgPrintLn(" ");

DbgPrintLn("Loop #" + String(lLoop));

//-- Go up

for (int i = 0; i < GMaxValue; i++) { lValue = i; analogWrite(GPinNo, lValue ); if ((i % GDbgFreq) == 0) { DbgPrintLn("Value: " + String(lValue)); } delay(GDelayStep); } //-- Go down for (int i = GMaxValue; i > 0; i--) {

lValue = i;

analogWrite(GPinNo, lValue );

if ((i % GDbgFreq) == 0) { DbgPrintLn("Value: " + String(lValue)); }

delay(GDelayStep);

}

//-- Set to 0 and wait a moment

analogWrite(GPinNo, 0 );

delay(5000);

}

Thank you!

[Lukas]

Hello Jan,

Arduino function analogWrite() does not set real analog value to a pin, but runs PWM signal with fixed frequency and variable duty cycle.

So with the standard MAXI you can have only 24 V PWM signal out of the output. (Please note that CONTROLLINO_A1 is analog input pin.).

And if you get 4,8 V, you obviously measure it at the pinheader, which is not correct – please use the screw terminals.

With the MAXI Automation the situation is better – there are two real analog outps there – please see our example.

Thanks,

Lukas