I bought a Winstar 144x32 LCD (WG14432D) because it was cheap and it would be nice to do some experiments with it. The main problem with this LCD is that it has no (working) library for it.
I already searched the whole Internet with Google, but my results were unimpressive:
https://forum.crystalfontz.com/showthread.php/7410-Tutorial-ST7920-Seeeduino-v4-2-Arduino-Sample-Sketch-Driving-a-144x32-Graphic-LCD (A huge example code which doesn't work. I set SCK, MISO and CS correctly and nothing happens.)
Knowing it has the ST7920 chip, I found a library for screens that use this same chip: https://github.com/olikraus/u8glib/wiki/device#st7920-192x32 (The library supports only other resolutions, such as 128x64, but I think as it's the same chip, it should work too. I also tried other screen variants of this same chip.)
On some portuguese site I found how to initialize and use the library properly: http://www.arduinoecia.com.br/2013/09/display-grafico-lcd-128x64-st7920.html (No problem for me, as I speak portuguese too)
U8GLIB_ST7920_128X64_1X u8g(6, 5, 4 ,7); to set the software SPI pins for the LCD. On mine (Arduino Mega) it would be:
U8GLIB_ST7920_128X64_1X u8g(52, 51, 53); //Enable, RW, RS [,RESET] (known also as) SCK, MOSI, CS
The result: The display stayed blank. Then I tried to use the hardware SPI initialization, which according to this site is:
U8GLIB_ST7920_128X64_1X u8g(53); // RS (known also as) CS pin needed only
Even so, the display won't do anything. It stayed light gray (Contrast adjusted) and that's it. No blinking, no switching on/off, nothing...
Finally, I was reading on this datasheet that the PSB pin must be set to 0 (ground) in order to enable SPI mode.
Other variants of those screen had jumpers or pins on the back, which you can jump to ground, but this one has none.
A high resolution image of the back of the LCD I captured (or atleast tried) and attached below (the front has nothing but the LCD), because I could find nothing about anything of this board. No schematic, nothing.
I couldn't find any PSB pin (which is identified as it), jumper ("JP") or similar on this board.
The pins to interface the LCD had no unusual pins which are identified as "PSB" or similar too:
Any suggestion or answer is much appreciated.