Olivetti Prodest PC128 ... wav -> K7

[Funesto]

Hello!
Sorry, I am not so good in French!

I am from Italy and I owned an Olivetti PC128. As you know it's aThomson MO6 Clone.

I found some old tapes, in which I may have recoded some "basic" basic code. I was about 7 or 8 at the time but I liked programming!

I found a DOS program to convert wav to K7 but when It find an error (ERREUR Somme + Checksum) it stops and I need to press a key to continue.

That's bad because if I leave my computer alone while working all night, I can't press a key if an error is found. Do you know if there is some option to add to dos line to keep con converting despite any error found?

And ... is it that bad a Checksum error in this case? There are just a few, does it mean that I will not be able to read/load my old files?

Thanks for your replies!

[Daniel]

Hello Funesto !

Can you make your .wav files available from a large file hosting ?
I'll try to convert them to .k7 files.

In case of bad checksum during conversion, the target file is unusable. Loading a file will stop with Error 53 (Device I/O Error).
In order to succeed, the .wav file must be corrected before conversion.

[Funesto]

Hi Daniel! Thanks for your reply!
You know, I am a DUMB! And now I just Speed-Up my DosBox emulator. I had some files that just ... It was a REAL flashback! I was so young ..

In the next days I will try to convert all my old analog own programs into WAV. I am using a chip chinese "Super Usb Cassette Capture" and Audacity

I record at 44100 16 bit stereo and then I join L+R channels before exporting at 8Bit!

It's a shame for those checksum errors...

what can you suggest me to "correct" Wav files?

Of course I could also upload my WAV files but ... all my old games are already in your DCMOTO Website ... so I am just searching for my old simple programs I wrote as I child!

P.S.

I Just can't load a program called "Distructor" I wonder what I had in mind at that time. Error I/0

[Daniel]

First you need a good tape player. These USB chinese cassette readers are not reliable, but sometimes they can work. Don't trust them too much.

Second, never mix left and right channel. The right channel contains the data and the left channel contains possibly audio, or just noise. Mixing the two channels adds data and audio, or data and noise, and makes the resulting signal unusable. Keep the stereo file at 44100 samples/second.

There is no magic recipe to clean the audio file. You only need to have a lot of experience. Faults have many causes : narrow bandwith, tape demagnetization, noise, irregular speed, and more. Sometimes you can repair with suitable filters, sometimes with speed variation, sometimes by hand to reconstruct some bits. This is not easy. Having two or more records for the same program can help. If a sequence is wrong in one it may be correct in the other and you can rebuild the .wav file.

In many cases you have to modify the decoding program for each particular case based on the errors found. This is why my decoding programs are not available from the dcmoto website. They are experimental and continuously modified.

[Funesto]

Thanks for your advices!
Unfortunately I Just can use that cheap tape player. But I am doing all from the start without joining the two channels!

Anyway ... off topic ... I Just can't remember how to split LIST command. lines just go out of the screen!

And thanks for Emulators!

[Daniel]

list.png (56.73 Kio) Consulté 5020 fois

[Funesto]

Thanks!!!!
I am at work and when I am alone .... I try extracting K7 files! Now I am trying with higher volume from that China Tape!

[Davide]

Buongiorno Funesto, volevo scambiare pareri, notizie ecc. per riversare i file k7 in wav correttamente

[Daniel]

DCMOK7 is a tool to convert .k7 files to .wav files. It is available here : http://dcmoto.free.fr/emulateur/index.html
It works with Olivetti Prodest PC128 cassettes without copy protection.
For copy protected cassettes please upload the .k7 file here as an attachment. I'll try the conversion.