Geeetech

Thanks William, checked all the voltages and they were fine, except for pin #8 (middle bottom pin onGR2560) for the LCD port #1.
It's voltage is all over the meter. Keeps recycling.

Hello, just bought Gt2560 board and hooked up LCD12864. Blinking LCD, and chirping just like so many others on here.
Yes I uploaded correct firmware ( tried various ones), commented out other display, reversed connections. Still does not operate.
Tried LCD on other ramps board and LCD works. Used ...