Atmos and Cumana won't boot until warm

[sonicmule]

Hi Everyone

I have 2 Atmos and a Cumana Reborn. My first Atmos works flawlessly with the Cumana and boots straight off the bat. I obtained a 2nd Atmos recently but I have issues getting it to boot with the Cumana connected (this Oric boots fine on its own).

First few attempts give random graphics flashing etc. After a while I get the status line saying insert a boot disk and then it hangs with random graphics.

Then finally the Cumana ROM will start to load but it will take a few more resets until the OS starts loading properly and auto running a disk.

Once all warmed up, it works fine and loads disks with no problem.

I'm using the supplied y adapter for power and have tried a 2amp and a 3amp 9 volt PSU. I've also replaced the three electrolytic capacitors in the Atmos, but still the problem persists.

What else can I check?

[Dbug]

No idea, but I'm interested in the topic because my Cumana Reborn is basically unusable on any of my machines, it works with some files and miserably fails booting at all with some others, which makes no sense since as far as the Oric is concerned there's nothing special about the HFE files on the usb stick.

[xahmol]

Bizarre. No ideas here, as my Cumana Reborn works absolutely flawlessly on both my Oric Atmosses (that also have been acquired seperately from completely different parts of Europe) with every valid HFE file I feed into it. (*knocks on wood*)

Power supply seems indeed the obvious one to check, but you already did so you say.

However, I do have a similar issue with my Twilighte Board. Exactly what you indicate: it needs warming up before it works on my first acquired Oric Atmos (and indeed similar graphic artefacts like you indicate without warming up), while running flawlessly on my second acquired Atmos.

But was it not Iss (or was it Rax) that was working on a board that would solve all those issues of instability connecting over that port?

[Chema]

No idea, but I'm interested in the topic because my Cumana Reborn is basically unusable on any of my machines, it works with some files and miserably fails booting at all with some others, which makes no sense since as far as the Oric is concerned there's nothing special about the HFE files on the usb stick.

I only heard of problems such as this once, and the CR was sent to Piotr for repairing. It was not me, so I might be wrong.

In any case, did you try with other USB sticks?

[sonicmule]

I've checked the voltage output on the regulator and got 4.97 volts when it plays up, but unfortunately I still get 4.97 volts when it's working. The other working all the time computer reads about 5.01 volts, but I think these voltages are with tolerance.

It just appears that the data coming in from the Cumana is scrambled and / or loading into the wrong address when the bootstrap is loaded in.

[Dbug]

No idea, but I'm interested in the topic because my Cumana Reborn is basically unusable on any of my machines, it works with some files and miserably fails booting at all with some others, which makes no sense since as far as the Oric is concerned there's nothing special about the HFE files on the usb stick.

I only heard of problems such as this once, and the CR was sent to Piotr for repairing. It was not me, so I might be wrong.
In any case, did you try with other USB sticks?

Yup, tried with at least three different usb sticks which all worked just fine with the exact same content when used on my Microdisc + Gotek setup.
Guess checking with Piotr is a good idea, except I'm not sure how to contact him, I bought it on Sell My Retro but I can't find the listing anymore.

[sonicmule]

No idea, but I'm interested in the topic because my Cumana Reborn is basically unusable on any of my machines, it works with some files and miserably fails booting at all with some others, which makes no sense since as far as the Oric is concerned there's nothing special about the HFE files on the usb stick.

I only heard of problems such as this once, and the CR was sent to Piotr for repairing. It was not me, so I might be wrong.
In any case, did you try with other USB sticks?

Yup, tried with at least three different usb sticks which all worked just fine with the exact same content when used on my Microdisc + Gotek setup.
Guess checking with Piotr is a good idea, except I'm not sure how to contact him, I bought it on Sell My Retro but I can't find the listing anymore.

You could try the Oric 1 and Atmos Owners FB group, he's on there.

[xahmol]

I bought it on Sell My Retro but I can't find the listing anymore.

https://www.sellmyretro.com/offer/details/40497
https://www.facebook.com/piotr.bugaj.18

[sonicmule]

Just read a post about the possibility of different brands of CPU and VIA causing some issues

The socketed Oric works with no issues.

[xahmol]

Well, the creator of the Twilighte Board (Jede) first thought that indeed different brands of the ViA chip or different combinations of brands between the VIA and CPU were causing these issues, but in the end they did not sufficiently explain all occurrences of not working vs working….
Especially also because according to the theory he than had it should have worked on the one that it did not work on, while my other had exactly the same VIA and CPU setup.

But did not follow-up with Jede on it for over a year now, so do not know if he actually solved that issue.

And of course that is not the Cumana Reborn, but the issues sound very similar to me.