BRT Community

Hi,

For these fonts, it is required to use CMD_ROMFONT. Please see section 5.70 in the Programming Guide for examples.
https://brtchip.com/wp-content/uploads/2025/07/BRT_AN_033_BT81X-Series-Programming-Guide.pdf

Here we set the font 34 to user handle 1.

cmd_romfont(1, 34);
cmd_text(60, 32, 1, 0, "34");

Hope it helps, Best Regards, BRT Community

Hi,
I'm working with a BT817 and I've encountered a strange issue with ROM fonts.
According to the documentation, the BT817/8 has built-in ROM fonts with handles 16–34, and fonts 31–34 are large ROM fonts encoded in ASTC 8x8 format.
However, on my system:
EVE_CMD_TEXT(20, 10, 31, 0, "BT817 Flash Image");  // works
EVE_CMD_TEXT(20, 10, 32, 0, "BT817 Flash Image");  // BT817 freezes
Font 31 works correctly, but as soon as I use font 32 (or any handle >31), the BT817 co-processor appears to hang (command FIFO stops progressing).
External flash is working correctly and is in FAST/FULL mode — I can read images from it without any issues.
I'm not sure whether I'll actually need these ROM fonts since I'll probably use custom fonts anyway, but I'd like to understand whether this is a known issue, a configuration mistake on my side, or possibly a silicon/firmware bug.
Thanks in advance for any advice.

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Our R&D team will be updating the tool to use the latest driver and we'll let you know when the version is released,

Best Regards, BRT Community

Hello,

Thank you for the update, I'm glad to hear that you have managed to get the conversion to work via the command line.

Yes the -q option in ffmpeg.exe relates to the quality of the conversion:
-q q                use fixed quality scale (VBR)
Best Regards,
BRT Community

No problem, but there seems to be a little lack of communication between FTDI and BRT it seems.

Thank you for your recommendation. I adapted the suggested lines, both for the input and output file paths, and it worked.

You cannot view this attachment.

It doesn't work from the EAB 4.1.0 window, but it does work from the command line. I should assume that this part of the instruction: -q:v 4
sets the file conversion quality to 4, is that correct?

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Hello,

Thank you for sharing the source video file.

Unfortunately the development team were not able to recreate the issue on their test machine.
They have asked for some logs of the EAB conversion process

QuoteCan we recommend the user open EAB's command prompt (by clicking the bottom button in left-side panel), run these command lines in turn and share the result log:

eab_tools video -i path/to/VAN.mp4 -r 798:450 -o "path/to/output" -q 4 -s 48000 -f 3 -c MIX -t 29.97

ffmpeg.exe -i "path/to/VAN.mp4" -threads 16 -hide_banner -y -s 798:450 -pix_fmt yuvj420p -r 29.97 -c:v mjpeg -q:v 4 -c:a pcm_s16le -ar 48000 -ac 1 "path/to/output/VAN.avi"

Best Regards,
BRT Community