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Re: repaired games from bad tapes

Posted: Sun Mar 24, 2019 12:50 pm
by .mad.
robcfg wrote: Sat Mar 23, 2019 4:54 pm That is because Diggem and Manybody ARE on the same tape, so they belong together.
i am sensing a little hostility in your tone... :?
fixing/modifying the files to make them work, is NOT my intention to annoy you or anyone else.

The CAS images (in the WOD archive) are split into two files.
the 2nd part Manybody has it's own separate CAS file (not on the same CAS image as Diggem)
which i assume it was on the original tape due to the very small size.

that manybody CAS file (in the archive) is BAD and will not load, as the manybody program file starts part way into that image.
it looks likes it has probably been recorded by pressing fast forward at intervals until the start of the file was found.
as it contains nothing but garbage before the start of the file.

Re: repaired games from bad tapes

Posted: Mon Mar 25, 2019 1:45 pm
by .mad.
Dragon Selection 2 (Dragon Data)[eng]
The CAS file contained duplicate data (A and B side merged) making it twice the normal size.
both of the data files failed to load for Beat the Dragon "data" and Music "yankee".
this is **possibly** caused by the WAV2CAS utility used to convert it.
I only had to correct the pause/gaps in the CAS image to fix it.

same problem with Dragon Selection 4
incorrect gap size between programs.
makes me think bad wav2cas conversion.

*Spanish version of selection 4 is working with correct gap sizes in the image.

Re: repaired games from bad tapes

Posted: Mon Mar 25, 2019 5:01 pm
by .mad.
Title: Dunjunz
Author: 2017-2018 Ciaran Anscomb
Publisher: 2018 Teipen Mwnci
Platform: Dragon, Tandy CoCo 32K
Run.tape: CLOADM
Run.dragondos: BOOT
Run.rsdos: DOS

Alternate (also working in emulator) version of Dunjunz.
the version in the archive does nothing in MAME or Xroar.
*MAME only works in Dragon 64k.

not touched by me, sourced online. 8-)

Re: repaired games from bad tapes

Posted: Mon Mar 25, 2019 5:27 pm
by sixxie
Heh, yes, I've tried to get Dunjunz replaced behind the scenes... The CAS on the site should work with anything as it's generated to include a slow normal loader if read naively with CUE data that overrides it to include the faster loader that's on the tape. And that's the official CAS ;)

If you want to distribute something extracted from the tape itself that'll work with things that don't support CUE, it'll have to be a WAV...

Edit: oh, that's weird about MAME Dragon 32. I'm reasonably sure it works on a real one...

Re: repaired games from bad tapes

Posted: Tue Mar 26, 2019 9:45 pm
by robcfg
.mad. wrote: Sun Mar 24, 2019 12:50 pm
robcfg wrote: Sat Mar 23, 2019 4:54 pm That is because Diggem and Manybody ARE on the same tape, so they belong together.
i am sensing a little hostility in your tone... :?
fixing/modifying the files to make them work, is NOT my intention to annoy you or anyone else.

The CAS images (in the WOD archive) are split into two files.
the 2nd part Manybody has it's own separate CAS file (not on the same CAS image as Diggem)
which i assume it was on the original tape due to the very small size.

that manybody CAS file (in the archive) is BAD and will not load, as the manybody program file starts part way into that image.
it looks likes it has probably been recorded by pressing fast forward at intervals until the start of the file was found.
as it contains nothing but garbage before the start of the file.
Hi,

I'm sorry, I didn't mean to be rude to you.

I'm just worried as I dumped a lot of stuff from the original tapes and wouldn't like to lose information in favour of commodity.

You can check my DragonBlock tool to help you identifying dumps that need to be corrected: https://bitbucket.org/robcfg/dgnblock_fltk

Cheers,
Rob

Re: repaired games from bad tapes

Posted: Wed Mar 27, 2019 12:07 pm
by .mad.
No worries. :D

that util, looks the business. 8-)
i am using a normal hex compare tool.

only the tapes (CAS files) that throw errors, are brought to my attention.
The more i examine these CAS files, the more i am convinced it is to do with the different CAS conversion tools used.
Various dumps of the same game have different pause block sizes (length of bytes) before and after a filename.
I have seen many random sizes... 1,2,10,352 bytes long.

when that gap/test tone is modified and fixed to 256 bytes long, they start to work in Xroar and MAME.
*which is all the editing i am doing in most cases.

reading the hex in the CAS, it has a FF (256 bytes) value at the start of the block with the ammount of data it is looking for.
I have seen a few tapes which have smaller value "F8" (possibly as part of a copy protection) where saving on real hardware would write the larger block (normal 256 size) so the resulting copy will fail (makes sense to me).

If the data (gap) in the CAS conversion is incorrect, then converting CAS back to WAV will probably fail in some cases.
but that all depends on the tools used.
Also if the CAS will not load in Xroar or MAME you can not use those tools to convert it back.

I guess a few tape players (real hardware) could still read and ignore this shorter gap.
As you could get various sizes with different tape recorder speeds writing to a tape ribbon that has been stretched overtime.
but i think the correct 1.1 size of 256bytes is the perfect "software" CAS dump.
a real WAVE tone could be longer or shorter, but i think a fixed length is what MAME is looking for.

Where the WAV version works but the available CAS doesn't.
converting the CAS again has worked for me in some cases (possibly from a newer redumped WAV).
so with every new WAV created the CAS should be updated to match.

if you only use WAV on real hardware, you won't have any of these problems. ;)

Re: repaired games from bad tapes

Posted: Wed Mar 27, 2019 10:52 pm
by .mad.
Beanstalker [Patched] (Orange)
*this is not the separate patch tape.

Re: repaired games from bad tapes

Posted: Thu Mar 28, 2019 4:22 pm
by admin
Thanks for tracking all these down - I am updating things offline and will sync the changes and clean up when I get a decent break from the day job.

Re: repaired games from bad tapes

Posted: Thu Mar 28, 2019 8:24 pm
by .mad.
admin wrote: Thu Mar 28, 2019 4:22 pm Thanks for tracking all these down
no problem. :)
i just made a GameBase of the complete WOD archive.
So i am currently load testing every game in MAME and Xroar, and editing the broken CAS files as i go.

here's one that failed to load in MAME.

Re: repaired games from bad tapes

Posted: Sat Mar 30, 2019 4:36 am
by Sarah
.mad. wrote: Thu Mar 21, 2019 5:27 pm just putting this here for reference.

Revolution Tape Copier (Paul Burgin).
protection check.

Code Word.
00 REVOL
01 UTION
...
Ha ha! Did you decode these or were they already posted somewhere? :geek: