替换 screen相关函数为屏幕驱动函数

static void Display_FPSTest()
{
    float Ftime, Ltime;
    float FPS;
    Ftime = millis();
    int i;
    for(i = 100; i > 0; i--)
    {
        screen.fillScreen(screen.Black);
        screen.fillScreen(screen.White);
    }
    Ltime = millis() - Ftime;
    FPS = 100.0f / (Ltime / 1000.0f) * 2.0f;
    screen.fillScreen(screen.Blue);
    screen.setTextSize(1);
    screen.setTextColor(screen.White);
    screen.setCursor(0, 0);
    screen.print(Ltime);
    screen.setCursor(45, 0);
    screen.print("ms");
    screen.setCursor(0, 9);
    screen.print("FPS:");
    screen.setCursor(25, 9);
    screen.print(FPS);
}