Hello I have one console and one slider. In the main loop, a character is inserted in console. GT1 timer update the slider current position. With #define GDISP_NEED_SCROLL TRUE defined in gfxconf.h , from time to time I can see a missing character on console, right after console scroll. If I move slider position fast, I see more lines with missing first character, and sometime touchscreen stop responding, until hardware restart of the board. #include "gfx.h" GTimer GT1; static GHandle ghConsole; static GHandle ghSlider1; uint8_t i=0; void callback1(void* arg) { (void)arg; gwinSliderSetPosition(ghSlider1,i); } static void createWidgets(void) { GWidgetInit wi; // Apply some default values for GWIN wi.customDraw = 0; wi.customParam = 0; wi.customStyle = 0; wi.g.show = TRUE; // Create the console wi.g.width = 50; wi.g.height = 200; wi.g.y = 20; wi.g.x = 20; ghConsole = gwinConsoleCreate(NULL, &wi.g); // Set the console colors gwinSetColor(ghConsole, Yellow); gwinSetBgColor(ghConsole, Black); // create Slider1 wi.g.width = 50; wi.g.height = 200; wi.g.y = 20; wi.g.x = 100; wi.text = ""; ghSlider1 = gwinSliderCreate(NULL, &wi); gwinSliderSetRange(ghSlider1,0,255); // Clear the console gwinClear(ghConsole); } int main(void) { // Initialize the uGFX and the underlying system gfxInit(); // Set the widget defaults gwinSetDefaultFont(gdispOpenFont("UI2")); gwinSetDefaultStyle(&WhiteWidgetStyle, FALSE); gdispClear(White); // Attach the mouse input gwinAttachMouse(0); // Create the widget createWidgets(); // initialize the timer gtimerInit(>1); //continious mode - callback1() called without any argument every 250ms gtimerStart(>1, callback1, NULL, TRUE, 100); while (1) { gwinPutChar(ghConsole,'0'+i%10); gfxSleepMilliseconds(100); i++; } return 0; } Does anyone can help me to understand what's wrong ? Kind Regards, Smd