"- install u8glib library in Arduino"
You don’t want this. This is for GLCD's not char based lcd's
"ultralcd_st7920_u8glib_rrd.h: line 38 #define LCD_PIXEL_WIDTH 20
line 39 #define LCD_PIXEL_HEIGHT 4"
You have just tried to define a graphical lcd of 20x4 pixels!!!! not relevant but I would put that back just in case
At a guess your cables are plugged in upside down (180 degrees around from where they should be)
There are two types of LCD connectors, identical pin outs but sockets are turned around 180 degrees. This normally isn’t an issue as they also provide an adaptor that has the sockets the correct way around for what ever system they are using. But when you plug it into a board that has its own lcd connectors... things get interesting.
Even the pictures on the site you linked show this.. Image four has bent over plugs, if you where to straighten up the plugs the key would face away from the green pcb. Now look at image six. The key is now facing the green pcb... ie backwards.
You don’t want this. This is for GLCD's not char based lcd's
"ultralcd_st7920_u8glib_rrd.h: line 38 #define LCD_PIXEL_WIDTH 20
line 39 #define LCD_PIXEL_HEIGHT 4"
You have just tried to define a graphical lcd of 20x4 pixels!!!! not relevant but I would put that back just in case
At a guess your cables are plugged in upside down (180 degrees around from where they should be)
There are two types of LCD connectors, identical pin outs but sockets are turned around 180 degrees. This normally isn’t an issue as they also provide an adaptor that has the sockets the correct way around for what ever system they are using. But when you plug it into a board that has its own lcd connectors... things get interesting.
Even the pictures on the site you linked show this.. Image four has bent over plugs, if you where to straighten up the plugs the key would face away from the green pcb. Now look at image six. The key is now facing the green pcb... ie backwards.