Help needed archiving Griffinsoft tapes

bbc/electron apps, languages, utils, educational progs, demos + more
User avatar
scarybeasts
Posts: 797
Joined: Tue Feb 06, 2018 7:44 am
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by scarybeasts »

scarybeasts wrote:
Tue Jun 08, 2021 9:36 pm
I'll try and get Doll and Drum loading. Again, it appears to have some wobbles that csw.exe can't deal with.
Well, here's something I've never seen before.

doll_and_drum_missing_bit.png

You can see a wobble, kind of a double peak, towards the lower left. That's a missing bit.
The bit isn't missing in the classic sense, which would be a volume drop-out. It's missing in the timing sense! As if someone has snipped 1-bit worth of time out of this WAV. It's detectable because the so-called 8N1 serial encoding of tape data (the default for normal beeb blocks) has a start bit (0) and a stop bit (1) surrounding every 8-bit byte. In the image above, it starts with a 2-cycle 2400Hz bit which is the stop bit at the end of a byte. Then there's a 1-cycle 1200Hz start bit for the byte that has the error.

Because the serial format allows this error to be located with some precision, I was able to fix it by looking at the peak gradients at the drop, and looking at how many bits are needed to re-align the start and stop bits. In this instance, the wobble should be 2 bits, "01". The fixes everything, including the eventual block CRC.

Unfortunately, this same situation occurs again (at least once; maybe more) later in the tape, and it's less clear what the missing bit should be. I've not attempted any further fixing at this time.

I was wondering what might cause this. Perhaps a micro-crinkle in the tape is eating a bit's worth of time? Anyone seen that?
Or could there be something in the WAV capture pipeline that isn't keeping up and is losing data?

Would you be willing to capture it one more time just in case? And if that gives the same result, I at least we know. Given that this title is MIA (best we know?), I'd be willing to try and recover the additional missing bits with what we've got. I love a bit of MIA recovery :-)


Cheers
Chris
User avatar
flaxcottage
Posts: 4635
Joined: Thu Dec 13, 2012 8:46 pm
Location: Derbyshire
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by flaxcottage »

Yes, of course I'll redo the Doll and Drum tape. I'll also check the tape integrity.

This cassette showed a lot of modulation as it played. I'll try a different tape machine too.

I'm studying the GRIFFIN loader code to try and get it to extract the needed code so that it can be saved. It is teaching me a lot of new tricks. :D :lol:
- John

Check out the Educational Software Archive at www.flaxcottage.com
User avatar
scarybeasts
Posts: 797
Joined: Tue Feb 06, 2018 7:44 am
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by scarybeasts »

flaxcottage wrote:
Wed Jun 09, 2021 9:54 am
Yes, of course I'll redo the Doll and Drum tape. I'll also check the tape integrity.
Thanks. Any ideas on the differences (or not) between side A and side B of these tapes? If they're the same, there's a chance the other side could be better...


Cheers
Chris
User avatar
vanekp
Posts: 1006
Joined: Thu Nov 30, 2000 7:09 am
Location: The Netherlands
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by vanekp »

Yes I did notice that there was drop out or dropped bits in the tape, as I also see and hear it in the lead in tone several times and did find it odd.
Regards Peter.
User avatar
flaxcottage
Posts: 4635
Joined: Thu Dec 13, 2012 8:46 pm
Location: Derbyshire
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by flaxcottage »

This is weird!

I wrote an answer to scarybeasts about an hour ago but it doesn't seem to have been posted. :?

Made new WAVs of Doll and Drum and posted at http://www.flaxcottage.com/wavs

The original tape had a number of striations visible, more towards side B than side A. Maybe that explains the extra modulation of the tape signal. However, the tape loads and runs OK with no missed data, as does a clone of the tape, on a real machine. It will only load in a BBC model B. The special GRIFFIN tape loader does not appear to work on a Master.

Still working through the code for the loader working out where to break into it to recover the separate sections of code needed to port this to disc. Do one and maybe can do all? [-o<
- John

Check out the Educational Software Archive at www.flaxcottage.com
User avatar
scarybeasts
Posts: 797
Joined: Tue Feb 06, 2018 7:44 am
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by scarybeasts »

flaxcottage wrote:
Wed Jun 09, 2021 1:56 pm
Made new WAVs of Doll and Drum and posted at http://www.flaxcottage.com/wavs
These latest WAVs have come out very differently from the previous ones. Unfortunately, just looking at them in an audio editor / viewer, it's clear they're not healthy. Playing them results in some very curious sound effects too.

Given that this tape is loading in to a real model B, there's probably something going wrong in your WAV capture pipeline somewhere. That's a shame because it'd be nice to have an archive of the unmodified / unhacked data.

I could still look at side B of the original captures, but I still don't have a sense of whether side A and side B have the same data or different data. How are the two sides of the tape marked / labeled?


Cheers
Chris
User avatar
flaxcottage
Posts: 4635
Joined: Thu Dec 13, 2012 8:46 pm
Location: Derbyshire
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by flaxcottage »

The tape has sides A and B labelled as such.

Side A should contain Toy Factory Level 1 and Toy Factory Level 2. From listening to the tape it would seem that both levels are in the one program.

Side B contains a creative activity.

You could well be right about my WAV creating method. My PC audio equipment is primitive to say the least. It looks like I need a good external sound card for my PC, one that will take input at a variety of levels not just Mic in and also one with an output amplifier that can be adjusted to match the Beeb's input.

I can clone the tapes and they work perfectly.

I tried hacking the GRIFFIN loader but found that it was really temperamental. There is a minute gap between the end of the GRIFFIN program and the rest of the code. It appears to be very time critical. Some of the loader appears to work in that I get a countdown display but I don't get the loading screen and memory appears to be empty after loading.

This is really frustrating. ](*,)
- John

Check out the Educational Software Archive at www.flaxcottage.com
User avatar
scarybeasts
Posts: 797
Joined: Tue Feb 06, 2018 7:44 am
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by scarybeasts »

flaxcottage wrote:
Wed Jun 09, 2021 9:25 pm
The tape has sides A and B labelled as such.

Side A should contain Toy Factory Level 1 and Toy Factory Level 2. From listening to the tape it would seem that both levels are in the one program.

Side B contains a creative activity.
Thanks. I might take another swing at side A if I get a moment of inspiration.

Back to "Odd one out", does this suggest that there's additional (different) data to be found on side B of that tape, too? I want to make sure I haven't done "half a job" here before moving on to fight "Doll and Drum".


Cheers
Chris
Coeus
Posts: 2226
Joined: Mon Jul 25, 2016 12:05 pm
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by Coeus »

flaxcottage wrote:
Wed Jun 09, 2021 9:25 pm
I can clone the tapes and they work perfectly.
By this do you mean simply doing an audio copy of the tape, i.e. the kind of thing with a dual cassette deck or with two cassette decks with the output of one connected to the input of another? If so, would it be worth making exactly such a copy and then posting the copy to someone who can try capturing it on different equipment?
User avatar
flaxcottage
Posts: 4635
Joined: Thu Dec 13, 2012 8:46 pm
Location: Derbyshire
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by flaxcottage »

Yep, sides A and B of both titles contain different programs.

I'd be happy to send the tapes to someone who can make WAV files. One has to be able to recognise one's limitations. :wink:

The programs aren't really amazing in themselves but they are MIA and ought to be preserved.
- John

Check out the Educational Software Archive at www.flaxcottage.com
User avatar
lurkio
Posts: 3616
Joined: Wed Apr 10, 2013 12:30 am
Location: Doomawangara
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by lurkio »

flaxcottage wrote:
Thu Jun 10, 2021 8:54 am
I'd be happy to send the tapes to someone who can make WAV files.
I can give it a go!

:?:
User avatar
flaxcottage
Posts: 4635
Joined: Thu Dec 13, 2012 8:46 pm
Location: Derbyshire
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by flaxcottage »

lurkio wrote:
Thu Jun 10, 2021 2:55 pm
flaxcottage wrote:
Thu Jun 10, 2021 8:54 am
I'd be happy to send the tapes to someone who can make WAV files.
I can give it a go!

:?:
PM sent. =D>
- John

Check out the Educational Software Archive at www.flaxcottage.com
User avatar
vanekp
Posts: 1006
Joined: Thu Nov 30, 2000 7:09 am
Location: The Netherlands
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by vanekp »

If the tape work fine on real hardware without a problem then something is not going right with capturing it in an electronic format, hopefully lurkio has more luck capturing them.
Regards Peter.
User avatar
scarybeasts
Posts: 797
Joined: Tue Feb 06, 2018 7:44 am
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by scarybeasts »

I had a go at Odd One Out, side B, but the WAV also appears to have missing bits.

Would be great to get all sides of all tapes to someone with a known-working WAV capture setup.
User avatar
flaxcottage
Posts: 4635
Joined: Thu Dec 13, 2012 8:46 pm
Location: Derbyshire
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by flaxcottage »

scarybeasts wrote:
Sat Jun 12, 2021 6:40 am
I had a go at Odd One Out, side B, but the WAV also appears to have missing bits.

Would be great to get all sides of all tapes to someone with a known-working WAV capture setup.
Lurkio should have the tapes today. :D
- John

Check out the Educational Software Archive at www.flaxcottage.com
User avatar
lurkio
Posts: 3616
Joined: Wed Apr 10, 2013 12:30 am
Location: Doomawangara
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by lurkio »

Tapes arrived! Thanks, John.

Had a heart-stopping moment when my hitherto reliable tape-recorder (Texas Instruments Program Recorder PHP 2700) went haywire and started chewing up the Odd One Out tape! :shock: #-o The recorder will now fast-forward and rewind, but if you try to play a tape it just spools it all out of the cassette and creates a mess of magnetic spaghetti in the tape bay.

But I think I caught it in time, luckily. Switched to a different tape recorder (Sharp Stereo Radio Cassette Recorder WQ-268E(W)), which seems to have done the trick:

Odd One Out.zip
(4.76 MiB) Downloaded 8 times

Doll And Drum is coming soon...

8-[

EDIT: Doll And Drum:

Doll And Drum.zip
(3.92 MiB) Downloaded 6 times

:idea:
User avatar
flaxcottage
Posts: 4635
Joined: Thu Dec 13, 2012 8:46 pm
Location: Derbyshire
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by flaxcottage »

Wow that was close! :shock:

Thanks a bunch Mr Lurkio. =D> =D> =D>

CSW files are just as good for archiving as UEF from my point of view. I'll upload the tapes to the educational archive over the weekend, thanks.
- John

Check out the Educational Software Archive at www.flaxcottage.com
User avatar
lurkio
Posts: 3616
Joined: Wed Apr 10, 2013 12:30 am
Location: Doomawangara
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by lurkio »

No problem!

Anyone got any advice about tape recorder maintenance (head cleaning, lubrication, etc.) that doesn’t involving taking the device apart?

:?:
User avatar
vanekp
Posts: 1006
Joined: Thu Nov 30, 2000 7:09 am
Location: The Netherlands
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by vanekp »

Hi Lurkio,

I a curious how you created the csw files?
the only one I am having problem making a UEF from is Doll And Drum A.csw I keep getting "A pulse is longer than the allowed maximum."

only if I try to redo the wav to csw the csw is not good which is why I was interested how you created them and with which program.

Below the uef of the ones I was able to make working uef's from.
Doll And Drum B.hq.uef
(3.24 KiB) Downloaded 2 times
Odd One Out A.hq.uef
(5.19 KiB) Downloaded 3 times
Odd One Out B.hq.uef
(4.57 KiB) Downloaded 2 times
Regards Peter.
User avatar
vanekp
Posts: 1006
Joined: Thu Nov 30, 2000 7:09 am
Location: The Netherlands
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by vanekp »

lurkio wrote:
Sat Jun 12, 2021 7:50 pm
No problem!

Anyone got any advice about tape recorder maintenance (head cleaning, lubrication, etc.) that doesn’t involving taking the device apart?

:?:
from the problem you are describing I think just cleaning will not help, sounds more like a belt problem or a problem with the clutch mechanism that drives the take up spool.
Regards Peter.
Coeus
Posts: 2226
Joined: Mon Jul 25, 2016 12:05 pm
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by Coeus »

lurkio wrote:
Sat Jun 12, 2021 7:50 pm
Anyone got any advice about tape recorder maintenance (head cleaning, lubrication, etc.) that doesn’t involving taking the device apart?
There is an enthusiasts forum dedicated to all things tape: https://www.tapeheads.net/~tapehead/forums.php

What you described earlier sounds like failure to wind the tape onto the take-up spool during play. If movement of the tape was driven by the take-up spool during playback the speed of the tape would not be constant. Instead it is driven by the capstan and pinch roller, an arrangement that does drawn the tape past the heads at constant linear speed. The take -up spool is normally geared, or has the appropriate size rubber belt, to enable it to rotate at the fastest speed it will need to, which is when there is almost no tape on it, i.e. at the start of playback. Then, to let it run slower than this, there is usually an arrangement that allows for some slippage, a kind of clutch. So there is a disc driven by belt from the motor (or directly on some fancy HiFi machines) and another disc that drives the spool separated by a piece of felt and pressure kept between the two by a spring. With age the felt can become compressed and smooth and not offer as much friction as it needs to.

Another thing to consider is whether the spool inside the cassette shell runs smoothly.

When the machine is doing FF or REW this clutch arrangement is not normally in force so a machine with borderline friction on the take-up clutch may struggle during playback, especially with a rather stiff spool in the cassette shell, and yet work fine on FF which is driving the same spool without the clutch. Then that stiff cassette may work fine in another machine which has a higher friction clutch and the original machine may work fine with a more smooth running cassette.
User avatar
flaxcottage
Posts: 4635
Joined: Thu Dec 13, 2012 8:46 pm
Location: Derbyshire
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by flaxcottage »

Doll and Drum has been added to the educational archive. Thanks for all the help guys. =D> =D>
- John

Check out the Educational Software Archive at www.flaxcottage.com
User avatar
scarybeasts
Posts: 797
Joined: Tue Feb 06, 2018 7:44 am
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by scarybeasts »

flaxcottage wrote:
Sat Jun 12, 2021 7:22 pm
Wow that was close! :shock:

Thanks a bunch Mr Lurkio. =D> =D> =D>

CSW files are just as good for archiving as UEF from my point of view. I'll upload the tapes to the educational archive over the weekend, thanks.
What a great collaboration! Thanks both.


Cheers
Chris
User avatar
lurkio
Posts: 3616
Joined: Wed Apr 10, 2013 12:30 am
Location: Doomawangara
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by lurkio »

vanekp wrote:
Sat Jun 12, 2021 8:11 pm
I a curious how you created the csw files?
I used the Windows GUI app “CSW Viewer”, which I believe calls out to the DOS program CSW.EXE:

0320D1D4-A779-4BA8-9435-73868E142C78.jpeg
A7C663CD-2229-4137-9F6B-74C632A3EC05.jpeg
0D93BE57-7A15-423C-8590-913B76B48988.jpeg
CFC7DCA1-8F05-45B1-BB50-BED1E2031FA6.jpeg
User avatar
lurkio
Posts: 3616
Joined: Wed Apr 10, 2013 12:30 am
Location: Doomawangara
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by lurkio »

Coeus wrote:
Sat Jun 12, 2021 8:37 pm
What you described earlier sounds like failure to wind the tape onto the take-up spool during play …
Thanks for the info!

:idea:
User avatar
flaxcottage
Posts: 4635
Joined: Thu Dec 13, 2012 8:46 pm
Location: Derbyshire
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by flaxcottage »

Just looking to archive Odd One Out and the program hangs at the same point each time it is run in BeebEm. The monster pushes the animal to pen 2.5 and then the program crashes.

This is the same whether the tape version or the disc version is used. The tape on a real Beeb works though. Very weird. :?

@Lurkio can you confirm the tape works on a real Beeb while you still have it?

Edit:
Just tried the disk image on a real BBC model B and that hangs in just the same way as in the emulator. Very strange.
- John

Check out the Educational Software Archive at www.flaxcottage.com
User avatar
lurkio
Posts: 3616
Joined: Wed Apr 10, 2013 12:30 am
Location: Doomawangara
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by lurkio »

flaxcottage wrote:
Sat Jun 12, 2021 11:19 pm
Just looking to archive Odd One Out and the program hangs at the same point each time it is run in BeebEm. The monster pushes the animal to pen 2.5 and then the program crashes.
Using my CSW of Odd One Out side A, I can't get it to crash — but I'm not sure exactly what actions I'm supposed to be performing to try to reproduce the crash..?

:?:
User avatar
scarybeasts
Posts: 797
Joined: Tue Feb 06, 2018 7:44 am
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by scarybeasts »

flaxcottage wrote:
Sat Jun 12, 2021 11:19 pm
Just looking to archive Odd One Out and the program hangs at the same point each time it is run in BeebEm. The monster pushes the animal to pen 2.5 and then the program crashes.

This is the same whether the tape version or the disc version is used. The tape on a real Beeb works though. Very weird. :?

@Lurkio can you confirm the tape works on a real Beeb while you still have it?

Edit:
Just tried the disk image on a real BBC model B and that hangs in just the same way as in the emulator. Very strange.
After the animal has been pushed and it stops, the cursor keys seem to work for me.


Cheers
Chris
User avatar
flaxcottage
Posts: 4635
Joined: Thu Dec 13, 2012 8:46 pm
Location: Derbyshire
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by flaxcottage »

This is bonkers!

Last night when the monster stopped the program was as dead as a Dodo. This morning when I switch on and check again it works!! #-o

Now, I know we have a rather playful entity living with us, one which changes HIFI settings, opens doors, etc. whilst we are not there. If it has got into my computer does that qualify as the start of Skynet?

Anyway, both Griffin titles are now archived on the educational website. :D Thanks again for everybody's help - two more MIA titles preserved. =D>
- John

Check out the Educational Software Archive at www.flaxcottage.com
User avatar
vanekp
Posts: 1006
Joined: Thu Nov 30, 2000 7:09 am
Location: The Netherlands
Contact:

Re: Help needed archiving Griffinsoft tapes

Post by vanekp »

And here is a working uef for Doll And Drum A
Doll And Drum A.hq.uef
(4.65 KiB) Downloaded 4 times
they are only using non stand block of 8n1 for the main program so nothing fancy to create the uef I used the command line : -
makeuef -iDoll And Drum A.csw -z 4 8n1

the -z 4 8n1 tells makeuef that the data from block 4 is non-standard data format @ 8n1 data format
Regards Peter.
Post Reply

Return to “8-bit acorn software: other”