I have a project using a Waveshare 1.5" RGB OLED display and an Uno board. It is hooked up using the SPI interface and works perfectly. I now want to do the same project using a Mega 2560 board instead of the Uno. Everything else is the same. I have connected the display connections like this:
VCC - 5v
GND - GND
DIN - Pin 51
CLK - Pin 52
CS - Pin 53
DC - Pin 50
RST - Pin 8
All of these pins are defined in the sketch as noted. Everything else in the sketch is the same as the Uno version. I upload to the Mega, with proper board selected in IDE, and it compiles/uploads successfully, however the display is completely blank. I have tried it with a second display and nothing. I have also verified the 5v on the Mega. I have tried it again on the Uno, with the proper pins defined, and it works. What am I missing here? I am using the Adafruit_SSD1351.h library. Any ideas?