BRT Community

With the update to the newer board software version, the board "Discussion - MCU" still does not show when you are logged in.
I only know that it does exist from checking the forum at work.
And it shows up when I open a private window in firefox.

That also means that there is no way to post in that board.
Like for example pointing out that the download link for the new ESE 5.0.1 is linking to the wrong file.
Edit: and I just downloaded and installed it now

Hello,

we'd like to offer the following explanations and suggestions:
1. Mismatch in RGB Bit Depth (OUTBITS Setting)
Some LCD panels, although labeled as supporting RGB888 (24-bit), may internally operate using RGB666 (18-bit). If the EVE IC's output bit setting does not match the actual bit depth supported by the display, it can lead to color distortion or visual artifacts such as noise lines.
Suggestion:
Please verify your LCD panel's actual color depth and ensure that the REG_OUTBITS register is configured appropriately during initialization to match the panel.

2. Avoid Using CMD_GRADIENT for Red-Sensitive Precision Areas
CMD_GRADIENT uses internal linear interpolation. In high-contrast or precision-sensitive areas—such as gradients involving red—it is prone to rounding errors that may cause visible banding or fine lines.
Suggestion:
Consider using a custom gradient image (bitmap) instead, and load it into RAM or flash to ensure consistent rendering and avoid interpolation artifacts.

3. Fine-Tune the Gradient End Color & Refresh the Cache
Using red values like 0xFF0000 (full red) can fall on edge-case transitions in RGB666 mode, leading to visual inconsistencies.
Suggestion:
Try slightly dimming the gradient end color—for example, use 0xF00000 instead of 0xFF0000—and observe whether the black line still appears.
Also, try calling CMD_CLEARCACHE() to clear the on-chip bitmap cache, which may help eliminate any residual rendering artifacts.

Best Regards,
BRT Community

Was this ever solved? I am having the same issue when drawing a vertical gradient from orange to red, there is always a thin black line towards the red end but not on any other colors across any of the other gradients I have done. Turns out this issue is across gradients and RECTS that use the RED color

Hi Rudolph,

Sorry for the delayed reply, Our new Programmers guide will be ready soon,

You are correct, the LVDS output is for one display only. We use two channels to allow us to support the high resolution panels such as 1920 x 1200, but the two channels work together to provide the bandwidth required. Therefore, they are not designed to support two separate display panels on one BT820B IC.

Best Regards, BRT Community

Ok, this got lost in the forums update, so I am trying to re-post.

Quote
On the programmers guide point, this is currently going through the final review stages and we hope to have it released shortly.

Hmm, how do I put this in writing? Just remember that I am not in a bad mood over here.
I has been over three weeks now with me checking every day if there had been an update.

And I was promised answers to my questions but this thread practically went on as a blog with close to no answers.
In the meantime you use for example the undocumented host command E7 in your own code - which I had not seen when it was put in 5 months ago since I try to barely look at your code, following the mantra that if it is not documented, it does not exist.
This is a tad bit frustrating.

Well now, there still is an unfortunate lack of available ready-to-use EVE5 display modules, none to be precise and I wonder why that is.

Anyways, here is something for the FAQs, maybe:

Can I use the dual channel LVDS output of the BT820B with two single channel LVDS displays?

No, first of all the output in dual-channel mode is interleaved, so one channel is sending the even pixels, the other channel is sending the odd pixels.
Then there is only one clock setting and one set of REG_SO_ registers, so even if the scanout engine could be convinced to output non-interleaved, it could only output the same information in parallel to two LVDS channels, so the same image on two identicle displays.

Is this an accurate assesment?
There is more, but this is probably enough on the question of using two displays with the BT820B.

Pls use the latest BT81x programming guide v2.6.

https://brtchip.com/wp-content/uploads/2024/11/BRT_AN_033_BT81X-Series-Programming-Guide.pdf

The offset is 0x188.

Unfortunately I can not repost directly, I am not making backups of the posts here. :-)
And I checked the wayback machine, no backup there either.

Well, now we know.

Hello Rudolph,


OK, so working again, thank you.

Apologizes, but I`m unable to restore them. Are you able to repost?

Best regards

BRT Community Admin

Well, let's try. :-)

Do you have a chance to restore the couple of posts that got lost?

Hello Rudolph,


We are working through updating the version. Are you able to post OK now?

Thanks

BRT Community Admin