I've tried to solder a 128x64 graphic LCD to my parallel port and a molex (for 5v and ground), exactly like on this drawing:
But when i connect the LCD to the molex, i get this on my lcd:
The left blue border's width is 4 pixels, then a 2 pixel wide white bar, and the horizontal bar is 7 or 8 pixels high (can't see it exactly).
The white pixels become dark when i turn the contrast to a normal setting, the white pixels are 'off', but the pixels i drew blue here don't seem to get power.
Sometimes, when the lpt plug isn't connected, random pixels go on and off on the lcd, and then there are 3 types of pixels:
- Pixels that are clearly on
- Pixels that should be off (appear a bit dark)
- Pixels that don't get power at all (don't change even if i set the contrast to it's highest setting)
When i try to write anything on the lcd, nothing happens.
I'm absolutely sure my LPT settings are correct, and quite sure too everything's soldered properly.
What could be the problem? Is the LCD just broken?
But when i connect the LCD to the molex, i get this on my lcd:
The left blue border's width is 4 pixels, then a 2 pixel wide white bar, and the horizontal bar is 7 or 8 pixels high (can't see it exactly).
The white pixels become dark when i turn the contrast to a normal setting, the white pixels are 'off', but the pixels i drew blue here don't seem to get power.
Sometimes, when the lpt plug isn't connected, random pixels go on and off on the lcd, and then there are 3 types of pixels:
- Pixels that are clearly on
- Pixels that should be off (appear a bit dark)
- Pixels that don't get power at all (don't change even if i set the contrast to it's highest setting)
When i try to write anything on the lcd, nothing happens.
I'm absolutely sure my LPT settings are correct, and quite sure too everything's soldered properly.
What could be the problem? Is the LCD just broken?
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