Setting Marlin for LCD problem (10 replies)

Hi guys! I open the topic here because I really think I have a problem with setting Marlin in order to have a functional LCD. So, I have a 2004 LCD 20x4 [www.aliexpress.com]. You can check in the link from where I bought it.

The problem that I have is that the LCD lights up and shows me only two rows of dots and no characters. This can be seen in the picture that I post it. I'm using a miniRambo Board with Marlin. I tested my LCD on a different miniRambo board from other 3D printer that has others setting in Marlin and it works. The problem is that I can't have access to that Marlin so I must to modify mine. When I tested the LCD from the 3D printer that works with my miniRambo and Marlin it shows me exactly the same problem. This tells me that my miniRambo and LCD are perfect functional and the problem that I have is setting Marlin correct.

What I have tried in order to solve the problem:
- adjusting lcd contrast
- switch the lcd cables ( default connection is EXP1 from LCD to P1 on miniRambo and EXP2 from LCD to P2 on miniRambo) but in this case does not even lights up
- install u8glib library in Arduino
- settings in Marlin: Configuration.h: enable line 975 #define ULTRA_LCD // Character based
enable line 984 #define SDSUPPORT
enable line 1128 #define REPRAP_DISCOUNT_SMART_CONTROLLER

ultralcd_st7920_u8glib_rrd.h: line 38 #define LCD_PIXEL_WIDTH 20
line 39 #define LCD_PIXEL_HEIGHT 4

If you have any opinions and you can help me please leave a messege guys. Thank you and Happy Printing!