Meurtre à grande vitesse, why there is not a TAP file?

[AmintaOric]

Hi all!

In these days I'm playing with my Erebus, loading TAPs file in memory from SD Card. I wanted to test the famous game "Meurtre à grande vitesse" but, reading the page that Oric.org dedicated to it (https://www.oric.org/software/meurtre_a ... e-129.html), it says: "mpossible to transfer to TAP file".

Why? Any chance to transfer it almost to .dsk?


Many thanks,

Davide

[mikeb]

"mpossible to transfer to TAP file".

Why?

I looked at the page you linked, it says it's available as an audio (WAV) transfer that works with Euphoric.

My guess would be that the original program includes some form of copy-protection, or something which is not correctly understood by the various WAV to TAP tools.

I don't think the TAP format can capture anything that's not a completely normal, regulation Oric data stream, it's just a file with the decoded bytes from the tape. Any tape that uses a special saver/loader that introduces weird stuff will be un-representable as a TAP.

[Symoon]

Mike is right! As usual
How do emulators (at least Euphoric) do to load a file on hard drive when you actually tell the Oric to load on TAPE ?
Well, they check the ROM calls for tape reading and catch them to replace them by hard-drive TAP reading.

But when a program (like MGV) uses its own tape routines (programmed by the authors), it's not using standard ROM calls, so emulators can't guess what's going on and replace the program by hard-drive TAP reading.

That being said, a way to make a TAP file would be to crack the program and replace the specific loading routines by standard ones. Which is exactly what Dom did a few years ago, in a superb effort to understand all the special routines.
So a TAP file exists, which changes as little as possible the original program, and have a TAP file.
I will upload it when I find a moment.

[ThomH]

I don't think the TAP format can capture anything that's not a completely normal, regulation Oric data stream, it's just a file with the decoded bytes from the tape. Any tape that uses a special saver/loader that introduces weird stuff will be un-representable as a TAP.

This I think is the strongest reason — that older emulators cheat in their handling of TAPs is sort of consequential of the data they can contain rather than vice versa.

Clock Signal at least also supports CSW, which is a fairly standard file format on other platforms, essentially encoding a square wave in RLE. It also treats fast loading of ROM data as an orthogonal issue from on-disk encoding, so a CSW of ROM-format data will load exactly as quickly as a TAP if fast loading is enabled and both will load at native speed if not.

WAV is a bit dodgy because technically it's only a container format. It can have arbitrary codecs inside — even the Sound Recorder provided with Windows 3.1 could output either a PCM WAV or a µlaw WAV, so they're not even as uncommon as emulator authors like to imagine. You can ignore the esoterica to an extent, but it turns into a usability hazard as you're claiming that you support WAV and you don't really. Just a subset.

[mikeb]

WAV is a bit dodgy because technically it's only a container format ... as you're claiming that you support WAV and you don't really. Just a subset.

I claim nothing! Not my tools, not my problem!

But you're absolutely right -- WAV is being used here in the context of WAV2TAP/TAP2WAV etc. which likely only understands PCM data of a limited number of channels/rates/bit depths.

The proper full MS WAV specification is full of all sorts of interesting stuff that only proper software, e.g. FFMPEG libraries, would bother with, I fully understand why someone wouldn't bother if was for jobs like this.

[ThomH]

WAV is a bit dodgy because technically it's only a container format ... as you're claiming that you support WAV and you don't really. Just a subset.

I claim nothing! Not my tools, not my problem!

Oh, sorry! That was very poorly worded. Read it "one is claiming to support WAV...". It was not meant to be a comment about anyone in particular, just a generalised comment, written with insufficient formality for text.

[mikeb]

Oh, sorry! That was very poorly worded. Read it "one is claiming to support WAV...".

No need to apologize, I got your meaning, I was just making a funny. Your point was absolutely right though.

(Disclosure: I have written can't-be-bothered "WAV" loaders for myself!)

[Symoon]

Quick update (sorry tired of re-writing the message with timeouts)

Meurtre A Grande Vitesse from Cobra Soft (1984), by Bertrand Brocard (with Marianne Alison, Gilles Bertin)

Nothing on inlay_b.


Version 1:
----------
Transfer errors unknown.
Special routines - impossible to transfer to TAP file with the usual tools, the program was left as a WAV file for Euphoric's Hardware Tape (F1 key):[mgv_wav.zip] (2 parts)
Dom managed to handle these routines (mixing fast and slow speed!), and made a TAP file: [mgv.tap]
See his explanations (in French) in his article: [Formats Exotiques _6_.pdf]

[mgv_v1_dikt.mp3]: This is the audio recording from side B (another hint for the game).
[codes MGV.pdf]: colour codes translated into their respective numbers by Dom.

The hints and manual are missing on the General Look picture. The Pearls are missing among the hints, too. See the Jeux&Stratégie review to have a general look of the hints.


2017-06-12 - Version 2 (V2):
----------------------------
Thanks to Stéphane Rezette and Didier Vallet, scanned another version, probably from 1985.

No transfer errors detected (tested with right and left channel).
The most curious difference is that the program is now unprotected! Saved as [mgv-v2.tap]

Other differences:
- "Oric 1 Atmos" appears on the front inlay, see [mgv_v2.jpg]
- the tape sticker now states "(c) 1985" instead of 1984
- the pearls are here, so they are scanned now, see [mgv_indice14.jpg]
- it seems like Cobra soft ran out of "L'eau de Mon St Michel" hints, and put photocopies instead of original [mgv_indice05_v2.jpg]
- apparently a new hint [mgv_indice13_v2].jpg), asking to use a real Minitel (French early version of Internet!) to go to Mico 7 magazine's server, where a hint is available. I tried to look in Micro 7 magazines, but none of the few I could read had a word about it. The server opened the 19th September 1984. The May 1985 issue (re?)reviews the game without a word for this hint, only speaking about an answerphone, apparently not related to Micro 7.
- the plastic part inside the box can now hold a tape or a floppy disk, when previous one could only hold a tape (see GL pictures).
- the "Diktaphon" recording is slightly different for the previous one, with heavy saturation on some versions, making it hard to listen to. [mgv_v2_dikt.mp3] and [mgv_v2-V3_dikt.mp3].

2017-06-12 - Version 3 (V3):
----------------------------
Exactly the same than V2, except the tape sticker is different (yellow). It also has the very heavy saturation recording of the "Diktaphon". [mgv_v2-V3_dikt.mp3]

[coolman66]

Always liked the look of the game and very pleased to see it in TAP format , but unfortunately it crashes out when i have i think to type in the colour codes , are they random , i dont read or speak French exept for the odd word , is there a way to solve this ?

[AmintaOric]

Quick update (sorry tired of re-writing the message with timeouts)
Meurtre A Grande Vitesse from Cobra Soft (1984), by Bertrand Brocard (with Marianne Alison, Gilles Bertin)

<edit: Truncated - Please people, don't do full quote of messages!>

MANY THANKS!

[jbperin]

Am I wrong or it is a game that requires to have to game jacket to play ?

At the very beginning of the game I'm asked to enter some color that are supposed to be found on the jacket.

You all have the code stuff ?

[Symoon]

@coolman66, @jbperin
The colour codes are on a grid on the inlay.
You can get the inlay on oric.org
https://www.oric.org/software/meurtre_a ... e-129.html
Connect, then scroll down the page to "stuff" section, the inlay is there.

[jbperin]

Connect, then scroll down the page to "stuff" section, the inlay is there.

ha yes !! it works .. thank you