Corrupt HDMI output

[sy2002]

On @JohanP9964 's HDMI monitor, the output of the core looks like this:

https://github.com/sy2002/zxuno4mega65/assets/6825267/71d0d940-88a3-471d-804f-cc2a30b936f2

We ruled our these things:

• HDMI backpower
• Wrong core version
• Corrupt core slot
• Core not starting (LED is green)
• SD card problems

Also interessting: The C64 core V5 works!

What we do not know yet: If VGA works. @JohanP9964: Please test with VGA and report back here.

@MJoergen Any clue what this could be?

[JohanP9964]

Hi. Tested today with two other different HDMI monitors, same bug

https://github.com/sy2002/zxuno4mega65/assets/110264207/517b02ca-5426-4eae-adf0-7002daab9103

However, connected to a VGA monitor it works perfectly

[sy2002]

@JohanP9964 Thank you - I highly appreciate your diligence and support. Great to hear that VGA works, that means that the core itself works and we "only" have a HDMI challenge.

Adding @amb5l : Adam, is there any chance that you can run the ZX Spectrum core through your HDMI analyzer? Here is the core: https://files.mega65.org?id=bdaeb7e0-9fc8-4185-99de-104d01229f27

[MJoergen]

@sy2002 @amb5l Let me give that a go (hopefully tonight). I'll be testing the latest HDMI audio fix anyway.

[amb5l]

To analyse the HDMI output I would need a data capture file - this is generated by connecting the HDMI source to a Digilent Zybo Z7 board. If you provide me with step by step (beginner) instructions I could try it with my MEGA65?

EDIT: just saw @MJoergen comment, I will wait for a data file from him.

[MJoergen]

@sy2002 Actually, looking at the original video in this issue, I was thinking: Could this be a reset problem? In other words, you might want to change line 268 in M2M/vhdl/av_pipeline/digital_pipeline.vhd to

reset_na <= not (video_rst_i or hr_rst_i);

I'm quite positive that this will fix the issue reported here.

The above line is a very recent change in the M2M framework, so you could also consider upgrading the ZXUno core to the latest M2M version. But the above single-line change can be performed regardless.

[MJoergen]

For reference, this is the corresponding commit in the C64 repo: https://github.com/MJoergen/C64MEGA65/commit/8c43b382b610eaafee615053e0cae7c7de62d236

[sy2002]

@MJoergen Cool! Thank you. I will try this and share a test build with @JohanP9964 .

[sy2002]

@JohanP9964 : Can you please test this experimental ZX Uno core: Does it fix the HDMI issue for you: zxutst.zip

[JohanP9964]

Hi everyone. It works now, great job :)

https://github.com/sy2002/zxuno4mega65/assets/110264207/7c18075c-e45d-4af7-9576-24b2c796e532

[sy2002]

Awesome - thank you @JohanP9964 for reporting this and for testing. You helped to improve the quality of the core. I will release an official update on the FileServer.