MP3 player file loading.

[Jamtex]

As i don't have the budget to buy another ZXpand and I was thinking of dedicating a unit to ZX81 / Spectrum homebrew games. I was thinking of looking at ways to load games onto a ZX81. On other machines like the Spectrum, it is possible to turn a .tap file into a .wav, copy this to a decent MP3 player with Rockbox and load it with a stereo to mono lead. So far it has worked with most things I have thrown at it including the horrible high speed Microsphere game loaders.

The ZX81 is not the best machine to load tapes on at the best of times, but is there a program to convert .p files to .wav files and has any tried to load them onto a real ZX81 using an MP3 player?

Thanks

[yerzmyey]

Hi,
there are some P2WAV convertors.
Here should be something
download/file.php?id=272
also You might check out this thread:
viewtopic.php?f=3&t=222&start=10&hilit=converter
Hope it helps somehow (have nothin' more, I'm at work now).
Greetz,
Y

[Rink]

Off the top of my head, I can't remember which tool I use. But I convert to wav and play through an iPhone or iPad as my only means of loading games into a ZX81 (don't have a ZXpand) so yes, it will work.

Actually, once you find that volume level (on the iOS devices it seems to be 'max'), I've found they load reliably.

[PokeMon]

Try to use the ZX81-IDE.
viewtopic.php?f=6&t=795

It can be used for transfering files to ZX81, creating WAV files from .p Files and development of software (assembler and prepared for used with BASIC, will do upload of a new version today or tomorrow). And it has the ability to choose a Fast Loader option. So you can transfer .p Files with speed of about 1kByte / second instead of the usual 40 Byte / second with standard speed.

Following hints from my side:

1. Be sure to connect EAR of ZX81 to your MP3 player output. It's in reality the MIC input but named with EAR by Sinclair (to connect "EAR to EAR").
2. Be sure to use a MONO cable for audio connection (if you don't use the provided original cable from Sinclair). You can use a stereo cable with mono adapters in same manner but mono adapters are needed on both sides.
3. Be sure to put audio volume to maximum value and if you use MP3 player for it to disable AVLS (automatic volume limiter system) in your MP3 player which is used to protect your ears. The EAR input in ZX81 need a very powerful signal.
4. Try to use maybe your PC onboard sound first, could have maybe more output power than your MP3 player. BTW, My connected audio system with speakers has less output at EAR out than my PC card.
5. If you use my ZX81-IDE try with Fast Loader "off" first - maybe the ZX81DEMO.p ("Transfer other file"). The output power is maybe reduced to 80% in Fast Mode, on my system. Fast Loader uses 15kHz and many sound cards have a filter which reduces output at this frequency a little bit. So if normal transmission is successful you can try the same with Fast Loader after.
6. It could take some time to find the best presets for audio transfer. Please take some time to try best.

Good luck !

[stefano]

May I ask you if converting to mp3 is too lossy ?
I've been trying again an again but I'm still in trouble, yet I need to find a way to disable the level limiter on my Creative zen (obviously the audio equalizer is disabled).
Note that I'm not using your IDE , I'm using the z88dk appmake tool, but since we're talking of it, do you mind if we borrow your fast loading option ?

[PokeMon]

Are you asking me ?
MP3 is a licensing theme but also don't have any codecs.
If you could provide me a working DLL for WIN32 for conversion I could use it.
But the question about usage / licence not to forget.
WAV format is free.

Anyway I think that MP3 will influence the transfer to ZX81.
Are you using the WIN assigned WAV player (which one ?) or just the internal transfer function ?
I had more problems with different media players except Windows Media Player.
All of them do not transfer WAV data without any transformation (e.g. VLC Media player doesn't work).
The internal "plain" audio of the IDE works better.

[stefano]

The point is that I couldn't convince my mp3 player play the wav files, but it could be consequence of the way I encoded them.. I must try your ide, no excuses

[PokeMon]

Yes you can try.
You should follow my additional hints in the tutorial thread, the first 3 postings only.

viewtopic.php?f=6&t=1064