These macros live in DisplayConfig.h
(override as needed):
#define PIN_DC 4
#define PIN_CS 3
#define PIN_SCLK 2
#define PIN_SDIN 1
#define PIN_RST 0
Use the convenience constructors that read from these defaults:
ST7305_2p9_BW_DisplayDriver lcd(spi); // 2.9"
ST7305_4p2_BW_DisplayDriver lcd(spi); // 4.2"