In this page I've placed a simple tutorial showing how to retrieve software for Commodore 16 and Plus 4 stored on tapes to be later on used with emulators, using a real Datassette and a sound board. Also are available some games retrieved from my old tapes using the procedure illustrated.

How to read C16 & Plus/4 tapes

First of all, a bit disclaimer, to protect the innocents :-)

OK, now we can start. Here's the list of what you need:

a Commodore 64 Datassette (model C2N a.k.a. 1530). If you don't have one, you can easily buy it used, for more or less 3$. You probably may also use the C16 Datassette, but you have to find by yourself the pin correspondence with the C64 Datassette connector. I don't recommend to use normal cassette players, because I've already used them with very low success. I think the fault could be of the stereo head that they use, which cause interferences between the two channels, even if I've tried to sample, in different ways, only from the left or from the right channel.

a +5 volt power supply, necessary to feed the Datassette. Obviously, you can use any other kind of +5v source, but be sure about its power. I don't know exactly the Datassette power, but I think that a current of 500 mA is really enough for it, even if actually I use a 1 A power supply. Warning: don't connect the Datassette to a source without knowing its power, such as sources given by the PC, you may damage both!

a sound board with audio line in, capable to sample at 44.1 KHz.

an headphone mono mini jack, or another type, depending on your line in socket.

the Minus/4 for DOS. This is a freeware C16/+4 emulator for MS-DOS made by Mike Dailly, that you can download from the Minus/4 home page. Also you can find there other versions of Minus/4, for Windows and Java, and other stuff relating to the Plus 4.

a sound editing program, like GoldWave or CoolEdit 96.

Once you have all the above stuff, the first step is to make a physical connection between the Datassette and the PC via the audio board. To do that, look at the next diagrams.

This's a top view of the C64 Datassette connector (note: wire colors may vary!):

...and this is its pins meaning:

With all the above informations, you should be able to make the simple connections necessary to send the Datassette output to the sound board line in. For this purpose, use this diagram:

To test if it works, just activate the power supply, but don't connect the jack to the sound board. You should ear the Datassette motor running, even though the play, rew or ffwd buttons are not pressed. If you can ear it, everything should be OK, but to be absolutely sure, use a multimeter to read the voltage between the two jack contacts, it should be almost zero (with no cassette inserted and the play button unpressed!). If there's no problem, you can safely plug the jack into the line in socket and proceed to the next step.

Now, it's possible to sample the data stored on the C16 tapes. Be sure that your sound board is set to record from the line in, then launch your sound editing program, start a new sound with a sample rate of 44100 Hz, mono channel and 8 bits of resolution. Insert the tape with the program that you want to retrieve into the Datassette, start the sample recording and... press play on tape :-). You should ear from the PC speakers or by looking at the program VU-meters if the data are correctly sampled, and try to understand when all the program have been read, this depends on your experience. Once you think that all have been sampled, stop the sound recording and stop the cassette too. Look at your sample, with a very close view (notice the time in the X axis), it should appear like this:

Notice that each "pulse" reach perfectly the top and bottom bounds. If your sample don't do the same, maybe you have to increase the line in recording volume of the sound board, from its configuration panel. Once you have a good sample, save it as a PCM RAW 8 BIT MONO UNSIGNED file, that's pure samples data with no headers. As name use what you want but with extension ".TAP", like "mysample.tap".

Now that you have the program sample, you can load it from the Minus/4 emulator. After you've read its manual and installed it, press F10 to access the file menu and select the ".tap" file previously saved. Now the situation is exactly the same like a C16 with a tape inserted in its Datassette. In fact, you've to type "LOAD" and press return, then when the messagge "PRESS PLAY ON TAPE" is shown, press the key F8 that simulate the Datassette's play button. When your game or program is loaded, you can run it by typing "RUN". To save the program, you can use the "freeze" feature of Minus/4 by pressing the key F9. Your program and its status will be saved as "test.fre", and you can rename it as you want to make other "freeze's" (otherwise, the last one will be overwritten). The frozen programs can be later on reloaded using the file menu. There are other ways to save the programs, read the Minus/4 docs.

That's all, I really hope it will work so nicely as for me! For more information, read the Minus/4 manual or visit its site, where are available other good informations about the tape sampling. And naturally, for any question, feel free to contact me.

C16 games