Tool/software:
Hi
We are currently using the SN65DSI84 with an I.MX8MM using Linux (6.6.y) . We noticed that static images sporadically move up and down (at such a high rate that the images seems smeared out over the full height of the display). If the problems do not occur in the first few seconds after initialization of the graphics pipeline, the image remains stable. However, when the display is unstable after the initialization, it also remains unstable until the pipeline is restarted. We also observe an image that is shifted o the right.
To debug this issue, we adapted the Linux driver to show the test pattern. The we noticed that the colors of the test pattern are incorrect. The white bars are gray. So, then we tried the other format (format 1 instead of 2). Then, the white bars of the test pattern are white. However, when we show our normal application image, the picture now looks blurry, while it looks fine with the old format. Is this caused by the DSI interface? Is the order of the bits standard for DSI? We have not observed the unstability, nor the shifted images when using the test pattern.
While we use the Linux driver, we compared the registers with the output of the DSI tuner, we were not able to notice any differences.
We also tried to measure the timings on the DSI interface, but as the DSI signals are not easily reachable on our board, we were not able to measure the timings on the actual board. We were able to measure the timings on another hardware design (our board's design is based on the other design, so the designs look similar), and the timings looked as we expected.
The registers of the sn65dsi84 also do not show any errors.
How can we debug our issues further?
