Hello,
I would like to kindly ask for some help in correctly configuring my LCD when connecting it to the Beaglebone (se the end of this post for details on what I am using). I have managed to modify the Linux source code which comes with TI's SDK and am able to get the LCD working but with a small, yet annoying issue. The image displayed on the display seems to have an offset. Half of the first letter is always lost (moved "to the left of the display") and half of the bottom line is likewise lost. So a negative offset is present both in x and y direction.
I would like to kindly ask for help in answering two questions:
- Is there a way to "calibrate" my LCD and correct for the mentioned offset and if so, how is this done?
- I noticed that changing the invert_line_clock member of thelcd_cfg structure (static struct lcd_ctrl_config) from 1 to 0 also affected the offset. At start it was set to 1 which caused a substantial positive offset. After setting it to 0 a small negative offset I described above appeared (so the situation improved but it's not yet perfect). Can anyone offer an explanation to why changing clock polarity caused this change? What exactly does invert_line_clock do?
Thank you!
I'm using:
- Beaglebone Rev A5
- ti-sdk-am335x-evm-05.06.00.00 (Kernel Version: 3.2.0 Internal PSP version (04.06.00.09)
- 7 inch LCD (datasheet of the used LCD is in the attachment)