GDemu: some games don't start

[Tackskull]

Hello there,

after 20 years of inactivity, my japanese dreamcast got a retro PSU and GDemu V5.20 mod.


SInce I prepared my memory stick for gdemu, most of the games run pretty well. But there are some specifics games (toy story 2, gauntlet legends and shadow man) in the USA versions that won't run.

Basically when starting this games, I get to the dreamcast bios presentation, than the "SEGA" screen, and then is like the dreamcst is resetting again get back to the bios, than back to the GDemu game list.

What i noticed is that all the games with this problem are the USA version, maybe because my dreamcast is japanese is not able to run them? But i run other american games pretty well. I even use gdemu card creator to patch all the games to be region free, but nothing changed. Probably as I will continue to test new games, I'll find other USA games wich will not run.

Can you guys help me with this? Thanks

[Nuisyda]

I encountered the same problem as you

[ateam]

1) Do some research on cleaning PSU pins as it relates to GDEMU (resets such as the ones you described sound somewhat consistent with the symptoms of poor PSU contact). There've been numerous posts and videos on the topic.

2) Ensure all of your TOSEC-format GDIs are coming from legitimate sources (see link list below).

Code: Select all

https://archive.org/download/tosecdcus20190822
https://archive.org/download/interludev1.0032003necinterchanneljp
https://archive.org/download/18wheeleramericanprotruckerv1.7002001segapalm4
https://archive.org/download/tosecdcapplications20190822
https://archive.org/download/tosecdcsamples20190822
https://archive.org/download/tosecdcmultimedia20190822
https://archive.org/download/tosecdcunverified20190822
https://archive.org/download/DreamcastCollectionByGhostwareMulti-region
https://archive.org/details/@manydumpedgames
https://archive.org/download/EF_GDI_Japan_Collection/Dreamcast%20GDI%20Japan/
https://archive.org/download/EF_SEGA_Dreamcast_GDI_Europe/SEGA%20Dreamcast%20GDI%20Europe/
https://archive.org/download/ef_SEGA_GDI_USA/Dreamcast%20GDI%20USA/
https://myrient.erista.me/files/TOSEC-ISO/Sega/Dreamcast/

[KorganBlood]

Hi, I have the exact same issue are there any more tips I can try? I tried both the TOSEC link above and the ones on the big thread in the download forum. As an example 102 Dalmations works fine. Aqua GT works fine. Some of my JP games like CC Sakura work fine. Most other games do not (as an example AeroWings 2), maybe 80-90% of games don't work. They just go straight to the bios menu after loading in GDEMU. If I put the Optical drive back in everything works (both GD-roms and CD's).

I have a GDEMU 5.20.5 firmware on a VA1 US. Running in non-US country so I have a power adaptor that I use. TV supports both PAL and the other signals (SONY BRAVIA Australia/NZ model).

I have tried with both VGA and analogue cables to the TV.

I have a sandisk 64GB and 256GB and both get exactly the same result. I tried 32k FAT32 on the 64 and 64k cluster on the 256GB.

I am using GD Menu Card Manager v2.0.0 downloaded from: https://github.com/sonik-br/GDMENUCardManager

Currently using stock PSU. I have taken a look at the PSU pins and they look flawless (and tried rubbing my fingernail along the edges and they feel super clean too). I am going to try rubbing them down but I don't have any alcohol at the moment. I also have a dreampsu laying around so I will give that a shot (only got a 12v 2a brick, waiting for a 3a one).

I have tried both GDMENU and OpenMenu. Same result.

I tried test_image = 0 and all the options in the option menu.

Once I have fully tested the DreamPSU to replace the stock I think I am out of options. Any other ideas? Am I making a basic mistake? I don't get why some games work and other don't. It is always the same games as well i.e. 102 Dalmations works 100% of the time. AeroWings 2 has never worked.

[Ian Micheal]

First thing every game works on gdemu so this is not the images unless your getting them from cdromance or some other place.. Where did you get these gdi files ?

[KorganBlood]

Thanks for responding Ian.

I downloaded them from this thread here: viewtopic.php?t=13313

I then specifically tried downloading Aero Wings 2 from the TOSEC set here: https://archive.org/download/tosecdcus20190822

For the TOSEC one I tried both shrinking it and not shrinking it.

Currently while I am debugging I just reformatted the SD and put a single game on there.

[KorganBlood]

Okay so I have tried cleaning all the pins and I have tried switching in a high quality 12v PSU I purchased. The result is still the same.

At this stage I think it has to be either the actual Dreamcast motherboard or a faulty GDEMU. I think the motherboard is okay because the disc versions of these games work fine.

Therefore I think my GDEMU is faulty. It is wierd how a few games work though. The majority do not. Is there anything I should look at on the GDEMU to fix it?

Does someone have a recommendation for me to buy a cheap replacement to test? I am thinking I will get a cheap 5.15b version of aliexpress?

[truemaster1]

guys do you rmember krizk? he said in order to eliminate psu contancts and rule out sdcard comatibility. to do the crazy taxi streess test. leave crazy taxi on the loop in the game play video for 7 hours straight. if the game wont freeze all ok. if freeze clean psu contacts and and try another sd card

[KorganBlood]

guys do you rmember krizk? he said in order to eliminate psu contancts and rule out sdcard comatibility. to do the crazy taxi streess test. leave crazy taxi on the loop in the game play video for 7 hours straight. if the game wont freeze all ok. if freeze clean psu contacts and and try another sd card

Thanks but I think that is a different issue. Games don't freeze at all. They either work or they don't even get past the initial DC whirly icon loading screen i.e. go straight back to the start menu. It is also 100% consistent i.e. the same games always work and the same games always fail. It is not the GDI images as well or the SD card as multiple sources and cards all have the exact same issue.

At this stage I think it is a faulty GDEMU and I have already ordered another one coming about 8 days so I will update if that fixes the issue

[KorganBlood]

Okay so my new 5.15 GDEMU arrived and I put the same SD card in there and everything works!!

So it sounds like my 5.20 GDEMU (which cost nearly 80 dollars over a year ago vs 30 dollars for the 5.15). Sadly because I had it in storage for so long it is too late for me to get a refund.

I have two questions. Has anyone heard of a GDEMU that only works in some games?!?! I don't get why my old one only runs a few games and the majority don't work. Is there someway to fix it?

My second question is Skies of Arcadia okay under 5.15? It is one of my favourite games but I don't mind skipping the intro if it works ingame or is it ALL video sequences don't work?