Jump to content

Intellivision music - Gradius II and Castlevania


Recommended Posts


I have been trying to learn IntyBASIC for the past few weeks and lately have been playing around with the music commands. I started with the music.bas example that came with IntyBASIC and have been swapping out the music with different songs. If anyone wants to look over the music or try it out on an emulator, I attached both the source and a binary to play with.



  • Like 6
Link to comment
Share on other sites

Very well done!


The IntyBASIC music player has a bit of a trade-off that I struggle with: drum capability requires speed to be 3 or 4, but a faster playback speed uses more ROM and also slows down the game. Uses more ROM because more music data, per length of time, will play compared to a lower speed. Slows down a game because the CPU has to be used to send more instructions to the AY.


Have you seen similar issues?

Link to comment
Share on other sites

It doesn't slow so much the games.


The drums operate starting at speed 4 (because M1 uses 3 ticks) and speed 6 if you use M3. (double fast M2), so not really needed to speed up your music.


The music always include space for the drums because the word oriented memory of Intellivision, so using drums doesn't use extra memory.

Link to comment
Share on other sites

Thank you! I honestly was not quite understanding how to produce great drum sounds, but did notice that when using m1 or m3 combined with low octave bass (Z), I seemed to get something closer to a drum sound. I was unaware of the tempo affecting the drum sound, but will need to play around with them more.


Trying to get songs playing at the correct speed has been a big challenge as well. It seems to be just trial and error. Between switching tempos, or even adding delays every so many lines seems to have helped get things where they need to be.

  • Like 1
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Create New...