Connections in SPI mode (only 6 wires between LCD and MCU):
#01 GND GND
#02 VCC VCC (5V)
#04 RS D10/CS or any pin
#05 R/W D11/MOSI
#06 E D13/SCK
#15 PSB GND (for SPI mode)
#19 BLA VCC or any pin via 300ohm
#20 BLK GND

Library code available here:
https://github.com/cbm80amiga/ST7920_SPI

If you find it useful and you want to buy me a coffee or a beer:
https://www.paypal.me/cbm80amiga

Music:
Hybris Title Music by Paul van der Valk
Performed by Tony Fluke Wiren