This might be a long shot, but I'm sure someone out there on this forum has seen the issue I'm having.
I'm working with a display that uses an ST7565R controller (not an Adafruit product, but it uses a similar LCD controller nonetheless). I tried to get support through their forums but it doesn't seem to be as active as this one.
I am trying to write larger letters via an FPGA, but when I try to make some different letters that use a lot of pixels in the same line, those pixels appear dim. Please see the attached picture for a much better description.
I was wondering if anyone has seen this kind of issue. I have plenty of power from my power supply available and all of the circuitry to boost the supply voltage is working fine. I have also tried a lot of different resistor ratio and volume settings to see if I could change the contrast. The contrast does change, but that does not create the same "darkness" for all of the pixels.
I am going to take a step back and try using the display on an Arduino just to see if it works properly with all of the examples there. That should let me know if I I have a damaged display and if I'm missing something in the commands of the display.