Black Screen in C64 Core

[FPGA64]

Core has not worked since I started, I have used every single video option in the ini file outputing over HDMI to a LG Oled TV. I tried a PC Monitor again via HDMI with the same result.

I have used the installer provided earlier on this thread with a different SD card. It failed, worked for the Guy who provided the installer.

I gave my files to another person who was helping and the files work fine for him and no output for me.

Its becoming something of an obscession with me. The C64 was my 3rd Computer, Zx81, Memotech 512 and then C64. So I would love to get it working again. But as I say Mister is free the core is free, I have many other cores to play with and I can always run VIce on the PC to play C64 games. I just got my hopes up again today when I saw the post about the boot roms.

[Hackshed_Carl]

Been on my C64 today and has no issues whatsoever
I only have a 32mb RAM module though

[Hackshed_Carl]

Daft question but have you made sure the RAM is connected to the correct ports on the DE-10?
There was another thread where the OP had incorrectly install it. Don't know if that helps but thought I'd mention it

[FPGA64]

The Mister runs The Bad Apple Demo on the Neo Geo and that requires the 128mb. The mister shows the 128 mb is installed, the Ram Test passes for over an hour at 140 and the new CPS2 Beta cores all work too.

I am fairly certain its not the Ram but I have no idea why I get a Black screen and others dont. I see the screen mode OSD show the C64 res and then darkness. Every other core I have run works so I have no idea what's special about the C64 core.

I read that thread and hoped it may be something simple but alas it was not to be

[mklcolvin]

I'm seeing the same exact issue. Version of C64 core is C64_20210426. This is from a fresh install of the mrfusion image. Has there been a fix for this?

[FPGA64]

To answer your question. No it was not resolved. Another person who had the same issue solved by cycling all the Nano Switches and returning them to the defaults. That didnt work for me

I did find out that Core C64_20171010.rbf worked. Anything later displayed the black screen issue

[Darthcustom]

I can confirm. Core starts up with black screen. I have to change to Standard C64 to boot. I moved boot.rom and boot3.rom files into C64/bootrom directory, but no change. Core was working perfect before. I'd move to older stable versions.

[akeley]

This core just underwent significant changes, check this out first: viewtopic.php?f=12&t=2566

It's one of my most used cores, I've played hundreds of games on it over the period of more than a year. Never had a problem, though I use a CRT TV so it might be different. Still, it's very odd that it's not working for only few people, since we're all using the same base hardware. Could some HDMI displays be "sensitive" to its output? Is it even possible?

[Chris23235]

I can confirm. Core starts up with black screen. I have to change to Standard C64 to boot. I moved boot.rom and boot3.rom files into C64/bootrom directory, but no change. Core was working perfect before. I'd move to older stable versions.

What is the boot3.rom? The core needs a concatenation of BASIC + Kernal.rom + C1541.rom. Have you tried to load you boot.rom manually?

The new version works for me as the older versions did. My old Rom was working as before (Jiffy Dos Rom) but I switched to the Dolphin DOS 2.0 Rom as it offers the fastest disc access.

[Darthcustom]

boot3.rom is to load a default CRT if I remember properly..... Now it has been replaced by OSD menu option

[FPGA64]

I can confirm. Core starts up with black screen. I have to change to Standard C64 to boot. I moved boot.rom and boot3.rom files into C64/bootrom directory, but no change. Core was working perfect before. I'd move to older stable versions.

What is the boot3.rom? The core needs a concatenation of BASIC + Kernal.rom + C1541.rom. Have you tried to load you boot.rom manually?

The new version works for me as the older versions did. My old Rom was working as before (Jiffy Dos Rom) but I switched to the Dolphin DOS 2.0 Rom as it offers the fastest disc access.

I have tried every possible variation of boot.rom. no boot.rom. The core has never worked for me as I say if I go way way back to C64_20171010.rbf it works anything after is a black screen. This is to Computer monitors, LG C9 TV and to a 1084 S

I have been given exact duplicates of peoples working systems and it fails for me but works for them.

The core is memory clocked at 64, the exact same as the Amstrad core and yet the Amstrad core works and the C64 wont boot. Jotego's memory testers run for hours without issue as does the Memory testing core at over 140.

I would dearly lovw to know why as the core was one of the main reasons to get a MiSTer

[Insert Disk Two]

This core usually doesn't work for me unless it is the first I load after I switch on the Mister.

[Chris23235]

I can confirm. Core starts up with black screen. I have to change to Standard C64 to boot. I moved boot.rom and boot3.rom files into C64/bootrom directory, but no change. Core was working perfect before. I'd move to older stable versions.

What is the boot3.rom? The core needs a concatenation of BASIC + Kernal.rom + C1541.rom. Have you tried to load you boot.rom manually?

The new version works for me as the older versions did. My old Rom was working as before (Jiffy Dos Rom) but I switched to the Dolphin DOS 2.0 Rom as it offers the fastest disc access.

I have tried every possible variation of boot.rom. no boot.rom. The core has never worked for me as I say if I go way way back to C64_20171010.rbf it works anything after is a black screen. This is to Computer monitors, LG C9 TV and to a 1084 S

I have been given exact duplicates of peoples working systems and it fails for me but works for them.

The core is memory clocked at 64, the exact same as the Amstrad core and yet the Amstrad core works and the C64 wont boot. Jotego's memory testers run for hours without issue as does the Memory testing core at over 140.

I would dearly lovw to know why as the core was one of the main reasons to get a MiSTer

Have you tried the Rom from the Github repository?

[FPGA64]

Yes I have tried that rom. A Jiffydos rom which I purchased and confirmed the MD5 with someone else. We had matching MD5. Mine failed his worked

[Chris23235]

Just a thought, have you updated your Mister Main to the latest version?

[FPGA64]

More times than you can imagine. I have now tried for asbout 40-50 hours in total over 9 weeks. Something about the core just doesnt like my setup.

[infected]

I tested the new version on my setup too. Still black screen and the the Mister locks up when trying to load a prg.

[Pulsar]

I tested the new version on my setup too. Still black screen and the the Mister locks up when trying to load a prg.

Have you tried downloading the new rom files posted below.

https://github.com/MiSTer-devel/C64_MiS ... r/releases

I had the same problem until I checked out the updated ReadMe. Now everything's working great again!

C64:

- DolphinDOS and SpeedDOS are provided (abandon-ware) as an option for System ROM.
- Other fixes and tweaks. Please read updated ReadMe!

Note: you have to update Main to latest one (or PRG loading will hang)!

[infected]

So i've tried the roms now and i managed to provoke the core to display some garbage for the first time in a while. I think i loaded DolphinDOS when this happened. Also reset the core from the menu a few times to get it to display whats in the attached image. Loading a .prg still locks up the whole mister. I use Update_All so i assume i have the latest main release.

20210507_152030.jpg (3.78 MiB) Viewed 6908 times

[Pulsar]

That looks familiar too. Something I've noticed, and it could be purely coincidental, but it's almost like the core is looking for, or wanting to boot from, a PAL environment exclusively. I didn't experience this happening anytime before the update.

I wouldn't necessarily call it broken, and per my settings, the core still runs great, but it does seem to respond better to my HDMI display *starting* in PAL mode, and then later switching to NTSC so I can then play on my CRT. Again, only during the loading of a .prg, .d64, and so on.

As odd as it sounds, try switching display modes and see if that works.

[rcade]

I have both an LCD attached to HDMI, and an analog board with RGB connected to a Sony PVM.

I will say that very often the core just shows a black screen for me on the HDMI out, but it always works on the RGB monitor.

[FPGA64]

I have both an LCD attached to HDMI, and an analog board with RGB connected to a Sony PVM.

I will say that very often the core just shows a black screen for me on the HDMI out, but it always works on the RGB monitor.

I wonder what this core does differently. I had a look at the Verilog but its beyond my current understanding

[infected]

Did a few more test switching hardware and video modes in the core. Still the same. Tried booting a few .crt's and those sometimes result in the C64 basic screen with random-ish characters around the screen (like in the screenshot). Sometimes something that looks something like a normal C64 loading screen with flashing colors. Sometimes a few SID bleeps and bloops. It's all very random. Just to repeat what i said earlier in the thread: every other core i've tested works just fine.

[infected]

HOLD IT! Todays (20210509) release suddenly started working. Other people that have had problems with black screen and other weirdness give it a try!

[FPGA64]

Todays release has fixed my issue I finally can load the C64 and enjoy the Sid and games

Thank you Sorg for all the work you have done.