Cumulus Issues

[metadata]

PEEK(#E4B6) reads 142 in my Atmos.

So you have the latest version.
Can everybody please check the version of your ROMs and write here if the cumulus is working or not.

There are 2 different version of the Atmos ROM.
http://www.48katmos.freeuk.com/roms.htm

[metadata]

i bought a eprom eraser and a few eproms. Time to check this thing with the ROM and test diffenrent versions on diffenrent oric's.

[Godzil]

And this is the video of cumulus working with my Atmos.
http://www.youtube.com/watch?v=aJwPHxLL-ps

@Godzil.. excuse me for my nescience.. what is Phi2 timing ? Is there a solution to get rid of that problem?

Don't worry, Phi2 is mainly the CPU clock, and it is used by the microdisc (and other peripheral) to know (at least) when the ULA need the memory bus to be free.

For the video you show it's seems to be some sort of memory corruption, I suspect caused by the cumulus. What happen if you press the NMI (reset) button of your oric when it's happen?

Another possible problem, the RESET trigger from the cumulus is too short, but I have serious doubt about this.

[Godzil]

PEEK(#E4B6) reads 142 in my Atmos.

So you have the latest version.
Can everybody please check the version of your ROMs and write here if the cumulus is working or not.

There are 2 different version of the Atmos ROM.
http://www.48katmos.freeuk.com/roms.htm

The two version only change between some tap function, nothing else seems to have changed between them

[peacer]

Oric reset button usually does not work if it hangs up in this way.

But sometimes oric hangs in kind of "responsive" way. For example, keyclicks are heard according to the pressed key type. Sometimes oric just quits from loading sequence and I get ready state in regular way, "non-dos" enviroment.

Now it looks like I have latest rom in Oric, qualified PSU and SD card. Cumulus boots and behaves nicely.

Any other ideas ?

[Godzil]

Could you please tell us what reworks was done in your atmos?

Photo of both side of the PCB will be the nicest option

[peacer]

What do you mean by "reworks"?

If you mean that, only intervention made to my Oric was replacement of failing ram chips and that was around ten years ago..

[Chema]

I think there were more than just two versions of the v1.1 ROM. Must have a look in my old files. Anyway, I do have one of the earliest versions (I think it is the v1.1a) and cumulus works quite nicely; except for the fact that I have to reboot a couple of times for it to start working properly (sometimes even the Cumulus itself hangs), and the problem I experience with the keyboard on some games from Twilighte.

However, indeed the changes were mostly on the tape loading routines (V1.1a still checked for parity errors, while v1.1b and c just ignored them). I don't think this should interfere with the Cumulus. At least not in the way that it cannot boot the DOS. But who knows.

I tried to make a small program to test the behaviour of the Cumulus vs the emulation of Microdisc. It measured the read/write errors to disk and overlay ram and I got none in all the attempts. I also tried to measure the reading/writing times, but I failed to do it properly so I have no reliable results. However it seemed to me that the timings where quite different in the real machine and in the emulators, and what seemed more interesting, in the real machine they seemed to vary quite a lot.

I don't know how Cumulus emulates the read/write operations, and also don't know if these varying timings may produce some kind of side effect. Anyone studying the firmware can bring some light to this?

[Godzil]

I think there were more than just two versions of the v1.1 ROM. Must have a look in my old files. Anyway, I do have one of the earliest versions (I think it is the v1.1a) and cumulus works quite nicely; except for the fact that I have to reboot a couple of times for it to start working properly (sometimes even the Cumulus itself hangs), and the problem I experience with the keyboard on some games from Twilighte.

However, indeed the changes were mostly on the tape loading routines (V1.1a still checked for parity errors, while v1.1b and c just ignored them). I don't think this should interfere with the Cumulus. At least not in the way that it cannot boot the DOS. But who knows.

I tried to make a small program to test the behaviour of the Cumulus vs the emulation of Microdisc. It measured the read/write errors to disk and overlay ram and I got none in all the attempts. I also tried to measure the reading/writing times, but I failed to do it properly so I have no reliable results. However it seemed to me that the timings where quite different in the real machine and in the emulators, and what seemed more interesting, in the real machine they seemed to vary quite a lot.

I don't know how Cumulus emulates the read/write operations, and also don't know if these varying timings may produce some kind of side effect. Anyone studying the firmware can bring some light to this?

I am not aware of version other than 1.1a and 1.1b of the Atmos ROM, but if you suspect you have another version, dumping the ROM is the only way to be sure. With the cumulus it will become easy to dump the ROM to a floppy and get it back on the PC, without even the need to unmount the ROM

When I speak about rework is the hardware changes done to an Oric, they could be multiple, like the official one on the reset line, tape or video output, or more "custom" like some changes on Phi2 on some OricFrance build device.

It is really important to know how and what your oric have inside, because anything could have an impact on the memory bus and the expansion bus.

Replacing the DRAM is one of thoses changes of course

[Chema]

I see. Well, as you say, the only way to know is taking pictures of the board and check.

I am not aware of version other than 1.1a and 1.1b of the Atmos ROM, but if you suspect you have another version, dumping the ROM is the only way to be sure. With the cumulus it will become easy to dump the ROM to a floppy and get it back on the PC, without even the need to unmount the ROM

I am not sure, either, but Fabrice Frances once told me he had a ROM v1.1c, but he did not recall the details about what was different. He also gave me a file he uses to check the different types of ROMs for the emulators. It includes the ROMs modified to support non-English keyboards in Euphoric and those modifications from Pascal Leclerc, but those are not official ROMs so I guess they are not important in this discussion. Here is an excerpt of this file (which, does not include his v1.1c ROM, as he told me, don't know why). It is in French, so I can only guess what it says

It includes some of those ROMs only used in Euphoric and for experiments along with a CRC to identify them in the .rom files. Just for the record.

Code: Select all

F18710B4	Basic 1.0 original
A65D6CED	Basic 1.1 original première mouture, appelé aussi Basic 1.1a
C3A92BEF	Basic 1.1 original deuxième mouture, appelé Basic 1.1b (ne compte pas les erreurs K7 pendant la bande amorce, et n'empêche pas le démarrage en cas d'erreur K7)
08E06953	Basic 1.1b modifié fourni avec Sedoric 1.0: au reset, n'autorise les interruptions qu'après l'installation des vecteurs
9FD687C7	Basic 1.1b modifié : utilisation du vecteur $0238 pour l'affichage.
6995DD24	Basic 1.1b modifié : PB5 préservé, chargement d'un programme Basic depuis la 2e rom (PB5Lib d'André)
72B14D15	Basic 1.1b modifié : avec indicateur de banque Telestrat (et affichage copyright)
603B1FBF	Basic 1.1b modifié : routine de clavier français (gestion AltGr, et chiffres avec SHIFT en mode CAPS)
1752DF63	Basic 1.1b modifié : routine de clavier français FR2 (gestion AltGr, et chiffres sans SHIFT en mode CAPS)
28B26D35	Basic 1.1b modifié : vecteurs d'interruption 65816, caractères compressés (tournés), routine clavier FR2
5F368A13	Basic 1.1b modifié : attributs 60 Hz.

303370D1	Basic 1.1b modifié : routine de clavier UK (gestion AltGr)
A71523AC	Basic 1.1b modifié : routine de clavier suédois (gestion AltGr)
47BF26C7	Basic 1.1b modifié : routine de clavier espagnol (gestion AltGr)
65233B2D	Basic 1.1b modifié : routine de clavier allemand (gestion AltGr)

[Godzil]

There is only 3 original and official ROM in this list, (the first three lines):

1.0
1.1 "a"
1.1 "b"

All other lines are non official ROM.

Modifié in french mean "modified" in english

[peacer]

Another sad update :

I've tried 3 other IDE cables to see if problem is due to IDE and still the same

I changed jumper settings in both cumulus and cumulusbus to use shorter cable. Again booting from cumulus leads to halt of oric and the same random character screens.

Anything left to do? Should I cry now?

[peacer]

Here are pictures from my Oric's PCB to reveal reworks...














And, back side.

[Chema]

Anything left to do? Should I cry now?

Difficult to say. Don't despair, someone with some hardware knowledge may help you. In your pictures I see one strange connection between a pin in the ULA and ground with a resistor that does not appear in the usual boards. Also there is a condenser and a resistor in one corner, but I think they appear also in Godzil pictures and I think I also saw them in other pictures.

Now about that cable and resistor in the ULA, I am not sure which pin it is connecting to ground. I count 7. Maybe it is connecting pin 7 which is the 12MHz CLK input?, maybe pin 14 which is the Phase2 clock generated from the input in pin 7? maybe pin 27 which is the R/W signal. The last option is a Data bus line, which I Doubt it is.

I am just guessing... please wait for a hardware expert to help.

EDIT: It is pin 7. Pin 6 is connected to GND and that can be seen in the picture. And it is not connecting it to GND, but to Vcc (which is at pin 24), or that it seems. Maybe a pull-up resistor? In any case that might add delays in the CLK signal, though not sure if that could affect Phi2 afterwards...

[peacer]

Thanks Chema.. I'll follow the advices..