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I'm trying to connect a Sharp LQ070Y3DG3B TFT display to an Epson S1D13517 display controller. The test image and a bitmap that I've loaded are showing up fine, except there is a aqua line vertically down the center of the display about 1 pixel wide regardless of what I try to display. To the left side of the aqua line is a strip about 5 pixels wide that the colors on the test pattern are incorrect except for green. Does this failure mode tell me something about what could be wrong with the software/hardware? How can I determine what is wrong with the display?

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    \$\begingroup\$ It sounds like your waveforms for driving the LCD are incorrect. Have you checked that ALL the set-up and hold times for every data line is correct? I had a project that had similar weird LCD artifacts, and it wound up being too-short inter-frame timings. Go through the datasheet, and verify that ALL the timings you are sending the LCD are correct. \$\endgroup\$ – Connor Wolf May 22 '13 at 5:49
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    \$\begingroup\$ I've seen this type of problem on graphic LCDs when one contact fails on the elastomer strip connecting the PCB/FPC to the contacts on the LCD glass. If your LCD uses elastomer strips for contacts as described above, have you tried opening up the display, cleaning and reassembling the elastomer strips? Sometimes nudging the elastomers will shift the problem to a different pixel row or column, confirming this hypothesis. \$\endgroup\$ – Anindo Ghosh May 22 '13 at 6:21
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The EPSON datasheet has an incorrect formula for calculating the value of the horizontal display width register (HDISP [16h]). The formula should read:
HDISP in number of pixels = ((REG[16h] bits 6-0)) x 8

Instead of:
HDISP in number of pixels = ((REG[16h] bits 6-0)+1) x 8

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