I got the 3.95" LCD from aliexpress which uses IL9488. I used the MCUFRIEND_kbv library. I am using an Arduino Mega as I need other GPIO to be used for other purposes. I can't use the Uno because of this limitation.
I have other modules like the DS3231, and ESP8266 connected to the Mega and this 3.95" LCD connected as well. ESP8266 is powered separately using a 12-5V converted supply. The Mega is powered using another source. The normal graphics test is working in the LCD. I am able to make it work with the Nano, Uno and Mega. Even for the Mega I am able to write customized messages.
What I intend to do is to update the time in the LCD which is received from the DS3231. It updates the LCD but I see a flickering issue here.
Every update (LCD display function is from the loop which sets the text when there is a second/time/hour difference in the time) seems like it draining more current as the one of the LED connected to Mega dims, the Rx/Tx LEDs also dim.
I am able to get the LCD refreshed but it shows a flickering. I powered the LCD 3.3V and 5V using another separate source but still the small flickering continues.
Moreover all these time I was connected to the Mega through the USB from the laptop. Once I unplug the USB, LCD starts and shows some update and again become white. This continues and an not able to see anything on LCD there after.
I am not sure why only when the Mega is connected to USB this LCD works and that too flickering but once the USB is removed the LCD is not working at all.
Can someone please do help me in this ?