I used the modul with external powersupply with 5V/1A over I2C. By setting the modul with setBackLight(100) or setBacklLight(12) it works normal.

By other values the Backlight will lighter and goes back to the value by using Print(Text).

The Backlight is flickering by using Print a Text.

 

The Firmware Version is 3.0.

 

 

#include <Timer.h>

byte Count;

Timer Timer1;

void setup() 

{

  Wire.begin();

  Timer1.every(1000,Timer_Secound);

  LCD_Clear();

  LCD_Font(201);

  LCD_Backlight(50);

}

 

void Timer_Secound()

{

  

  LCD_Text(50,50,"123.4",201);

}

void I2C_Befehl(char Befehl[],byte Address)

{

  Wire.beginTransmission(Address);

  Wire.write(Befehl);

  

  Wire.endTransmission();

}

void LCD_Clear()

{

  I2C_Befehl("CL",0x27);

}

 

void LCD_Backlight(byte Light)

{

  Wire.beginTransmission(0x27);

  Wire.write("BL");

  Wire.write(Light);

  Wire.endTransmission();

}

void LCD_Font(byte Font)

{

    Wire.beginTransmission(0x27);

    Wire.write("SF");

    Wire.write(Font);

    Wire.endTransmission();  

 

}

void LCD_Text(int X, int Y,char Text[],byte Font)

{

  Wire.beginTransmission(0x27);

  Wire.write("SF");

  Wire.write(Font);

  Wire.write("ETP");

  Wire.write(X);

  Wire.write(Y);

  Wire.write("TT");

  Wire.write(Text);

  Wire.write(0x0);

  Wire.endTransmission();  

}

void loop() 

{

  Timer1.update();

 

 This is the bug in Microchip MCU, the PWM will be paused when changing the MCU freq.

Our firmware was modified to deal with this bug since V3.3, in older firmware, the MCU freq will be dropped from 64Mhz to 8Mhz immediatly when no data received to save power, and in V3.3, we drop the freq step to step to try to reduce the flicking after a period and also can save the power.