MS2109 Horizontal Front Porch adjustment

[HotelMoted]

Hey I was wondering if there was a way to lessen the "Horizontal Front Porch" with ms-tools? I got this black bar on the left side of the video signal, and I was trying to figure out if I could change the EDID information to move the entire video stream a bit to the left?

[HotelMoted]

I have already tried to rewrite the edid, but apparently it does not take effect, see how the circles on the right are cut off and there is a black bar on the left edge of the screen, is there a way to fix this?

[BertoldVdb]

Hello,

How did you change the EDID? To change it at runtime on the MS2130 this should work:
./cli --log-level=7 write-file RAM 0xf900 edid.bin
The edid.bin needs to be 256 bytes, you cannot verify the write as you only read zeroes

It is also possible to change it in flash, I now know how to recalculate the checksum and will post this in a few days.

Sincerely,
Bertold

[msbroadf]

Did you manage to figure out how to recalculate the checksum for the firmware on the MS2130?
I would like to change the serial number of the chip (all seem to report 20210621 as the serial)

[markvdb]

@BertoldVdb we'd also be very interested in learning about the ms2130's checksumming algo and/or a ready-to-go implementation. Might come in handy for the new FOSDEM video boxes...

[BertoldVdb]

I was a bit busy, here is the checksum calculation code: https://github.com/BertoldVdb/ms-tools/blob/main/mshal/ms213x/csum.go

[FallingSnow]

Does changing the edid using ./cli --log-level=7 write-file RAM 0xf900 edid.bin work for the ms2109 as well?

[BertoldVdb]

I am not sure, you can try it... In any case you can replace the EDID in the EEPROM easily on MS2109.

[FallingSnow]

It didn't seem to work. I wrote the edid to f900 and tried unplugging and plugging in the hdmi connection. No edid change.