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Creating the tape / CDT file

A topic by KrakenDev created 79 days ago Views: 185 Replies: 8
Viewing posts 1 to 9

Hello everyone,

So far I have been creating a disk once my game was compiled and tested it so (with the 64k limit in mind of course).

I'm not using cpctelera or any other framework and so here I am, slightly stucked to create the CDT file as I can't find any tool online (links are all broken). Best I could find is the source for 2CDT but I don't think I will have time to look into that, if you know what I mean (end of jam panic mode :D).

Any idea where I could find a binary for Windows?

Thanks in advance!

Jam Host

Hi KrakenDev,

   If you download CPCtelera 1.5 (current development branch) and look into the cpctelera/tools folder (no need to install it), you will find both 2cdt and cpc2cdt tools to create CDT files out of binaries. Both of them are in source code form, but both of them should compile under GCC/CLANG either on Linux, MacOSX, Windows/Cygwin, Windows/WSL or Windows/MinGW. You can compile them in your preferred environment and use anyone of then to produce your CDT. You don't need to install Cpctelera for this: just pick both tools' sources and use them as needed.

  Good Luck with these latest hours :)


Contact me if you still need help. 


Thanks Pat. I ended up using javacpc, there is actually a tool inside to convert disk to CDT. I didn't get the time to test if the tape was working though. We'll see. Fun fact: while owning a 6128 from 1988 until today (yes I'm that old), I never got the chance to use a 464... So I actually didn't know how to load and start games from tape until today :D


Ok I tried the tape today, and it does not seem to work. After some digging it seems that's because I put the .bin file at the beginning of the tape (which sounds like the logical things to do). I recreate the tape with the .bin at the end and it works now. 

Would it be possible to update the tape file?

Jam Host (1 edit)

Hi KrakenDev,

    We know these things happen, and we also know you did an effort to try to enter in time to the contest. We very much value your intention to participate, and your  consideration of the contest. However, the rules must be the same for all participants. Other participants also have bugs they'd love to ammend, and there are always reasons to accept changes. As organizers, we feel that is much fair to completely freeze all content after deadline, than drawing arbitrary lines to let some participants update their contents, and some others not. Therefore, as we stated in the rules, content is freezed, no update is possible.

   Apart from that, I understand that you made an effort to enter the contest and had to push hard against time. This probably lead you not to carefully review the rules of the contest, which clearly state:

  • Games must load into memory in a single pass. Several loads are valid before the start of the game. Once the game starts, no more loading is permitted. Therefore, only 64K of RAM will be available for any game during execution.

   We have reviewed your game, and it loads new data every time you pass a world. Apart from your CDT not working, this feature of your game is against the rules.

   As I said, we very much value any effort from any participant, and we also have enjoyed testing your game. However, we shall mark it as disqualified, for the reasons discussed.

Hope you understand our decission, even knowing that it will probably be frustrating for you. Sorry about that.

Submitted (2 edits) (+1)

Fair enough, I actually completely missed that rule... Or I read it as "the game must run in 64k" :) (and to make it worse the loading actually loads... nothing! Simply the same level that is already in memory, I was just coding ahead for new worlds for a later version ^^).

If I have just one single feedback for the next jam, that is is to provide more information and tools to create CDT files. I lost the biggest part of  the last day trying to get that to work. I didn't imagine a second it would be such a hassle :(

Thanks for organizing the event, I had fun! (and my "level designer" John Random too)

(2 edits)

Hello KrakenDev,

I encourage you to finish your game, as you would have done if you had had enough time, and publish it.

Last year my  game Dr. Roland was disqualified because it looks too much like Nintendo's Dr. Mario.
After the natural disappointment, I let some time pass, and resumed development, fixing some bugs, polishing the controls, and adding more hazards.

Finally, about three months ago I published it here on and CPCWiki, and it became a great success, for my humble career as a CPC video game developer  :-)

It has been dowloaded more than 700 times, several youtubers have played online with it... and, currently I feel very proud of it.

So, go ahead ... let some time pass, and after that  finish your game, as you like, and publish it.


By the way, here it is Dr.Roland, in case you want to try  (

Submitted (1 edit)

Hi John!

Oh I actually really like Dr Roland but didn't know it was originally disqualified too....

To be honest, I don't blame anything but me and since the experience of coding everything from scratch was great anyway, I'm don't mind.

I'll make AMSTRED into a full game later this year (even though I'm good at "almost finishing" my games ahah, time to change this bad habit).

Thanks for the kind words!