hi, i've build a PIC burner and my first core modul. burning the bootloader and uploading the mios working without problems. but the LCD AV1624 2x16 shows nothing. also the backlight is off. but the pins 15+16 for BL are about 4,9V. D0 has 4,9V D1-D7 0V. what can be wrong? display failure? any other tips?