(122 replies, posted in Commodore Computers)

Hi! I managed to track down the bug now thanks to your report. Not sure exactly when I will have the time to actually fix it, but at least it is within reach now. I won't do any promises here, but hopefully I'll fix it within a week or something.

A command to change the multispeed setting is — unfortunately — not very likely to be included since the multispeed stuff is actually handled by the editor (e.g. by the code that calls the player code) rather than the player code itself. Therefore such tunes wouldn't work when played outside the editor, e.g. after packing them. It is a reasonable request though and of course I see that it could be useful in some ways if it would have been implemented.


(122 replies, posted in Commodore Computers)

Wow. smile Now that is clearly the most detailed and thorough bug report that I have ever received in relation to defMON. It certainly helps. Thanks for that! smile I'll try to look into it as soon as possible. The next version will also include some small bugfixes related to stereo SID stuff.

Also good to hear that you enjoy using defMON.


(122 replies, posted in Commodore Computers)


Not sure why one would use such an old version as 20090304 (8 years ago) at all? In general it is advisable to always use the latest build.

Regarding the pattern end-marks, I've noticed this bug from time to time as well. However, it very rarely happens to me myself, whereas for some ppl it seems to happen more often. This bug really confuses me and I'd be happy to get more detailed information that could help track down when it actually happens. The way you describe it here, you seem to imply that it *always* happens to you? Is that really true?

About copy+paste after loading/saving tune, I haven't experienced that myself. Again I'd be happy to get more detailed information on when this might happen. It sounds like something that could be related to the first bug, e.g. that the copy/paste routine freaks out when no pattern end-mark is encountered.


(122 replies, posted in Commodore Computers)

defMON isn't actively developed, but I wouldn't necessarily say that it is dead. You may still see occasional bug fixes and possibly still some additions of features though I don't make promises.

See PM about the wiki registration.


(122 replies, posted in Commodore Computers)

Not at the moment, but it is not entirely impossible that it might some day. It wouldn't be an awful lot of work to make defMON work with an interface like that (if I'd only find the time). I'm not making promises though.

What you're linking to is a standard MIDI interface for the C64 and they are quite straightforward to use from a coder's point of view. There is a whole family of MIDI interfaces for the cartridge port that all more or less work the same way. You can see a list of those interfaces here, and the DATEL one is included there:
https://codebase64.org/doku.php?id=base … interfaces

Just a few years ago there was also a MIDI cart called something like Kerberos MIDI developed, but it is now sold out. That one was also similar to the midi cartridges listed on that codebase page if I remember correctly. Not 100% sure though as I never really looked into that one.

The only "problem" is that in these days most people use something like a 1541 Ultimate cartridge or similar that occupies the cartridge port, so from that point of view using the cartridge port for MIDI connectivity isn't really desirable. This is also the main reason for making that defMON sync interface for the user port instead, since that one is not used by other hardware on most people's C64 setups.

There are also other benefits of having a cartridge like Action Replay, Final Cartridge or Retro Replay in the cartridge port (which is what you would have if you've got a 1541U2 sitting in the cartridge port). For example, defMON makes use of the built in fastload/save routines in these cartridges if they are present. That makes loading/saving tunes a whole lot faster.

Personally I'd much rather see new batches of Scannerboy's sync interface. That one was affordable as well.


(122 replies, posted in Commodore Computers)

clickclack777 wrote:

Any chance that DEFmon could support ASID in a future release so I can sequence the SIDStation through USB > MIDI from VICE running DEFmon on OSX? Thanks for amazing job so far.

Not really, I'm afraid. Furthermore, the version of the sync interface that has been released is precisely just a sync interface, and does not send the full set of midi messages. Only the midi sync message (and probably start/stop too I think — can't remember the details right now). Maybe I misunderstand the question. I'm not really familiar with ASID.

I suppose you could convert your finished defMON (not DEFmon wink ) tune to the common sid file format that is used in the HVSIDS collection and play it on your SIDStation the way you would play sids from the HVSIDS collection. Not sure how well it would work.


(122 replies, posted in Commodore Computers)

clickclack777 wrote:

Hi, I want to buy a Defmon sync adapter if anyone wants to sell theirs. Please PM me.

I don't have one to sell unfortunately, but just wanted to make sure that you've seen the following:

scannerboy wrote:

Hey, unfortunately I dont have anymore units left sad If it would get enough interest I could make a new batch. Send me those PMs!

Would be nice if enough interest for a new batch was generated. smile

By the way: I think I fixed the defMON wiki to work as it should again.



(122 replies, posted in Commodore Computers)

Yes, something happened with the wiki last night when I updated the wiki software. Unfortunately I have no time to fix that right now, but in the meantime, the direct link to the BPM calculator is:


garvalf wrote:

There are also a couple of cool native software you can use with Atari ST emulators, like MaxYMiser or Defmon (they won't create AY or YM files, but SNDH which are tied to the atari st capacities)

Since defMON is an editor for the Commodore64 and its SID chip, it most definitely won't work on an Atari ST or produce SNDH files. Just had to point that out.


(122 replies, posted in Commodore Computers)

I added DUBCRT now!


(122 replies, posted in Commodore Computers)

I added a little section on the defMON wiki about the little known "Super Command" mode of defMON:

It is very brief, but it may at least give a little hint about how the Super Command mode works.


(122 replies, posted in Commodore Computers)

Well.. hehe.. Best option is to use the VIDEO port for sound output. There is also some general info on SID noise here at codebase64:


Tried the latest Mac OSX build, and it crashed with the error:

Dyld Error Message:
  Library not loaded: /usr/local/opt/sdl/lib/libSDL-1.2.0.dylib
  Referenced from: /Users/USER/Downloads/Schism_Tracker.app/Contents/MacOS/schismtracker
  Reason: image not found

Of course I understand that all I might have to do is precisely to put that library file there, but I just wanted to mention this.


(122 replies, posted in Commodore Computers)

I just wanted to mention this stereo SID unit:


The reason is that I think that project deserves all the support it can get. I'd say it is the ultimate stereo sid solution. At least as "ultimate" as it gets in actual practice. Among other things it allows you to put any SID model(s) in any C64 (such as new SID on old breadbin, or one of each SID model, or whatever). Perhaps I should also say that I am not affiliated to that project, but merely a customer. It might only be produced in one batch, so if you want it, this is your chance.

It works with defMON, and when and IF defMON 2 becomes reality, it will certainly support this thing too, including the special features.

garvalf wrote:

DefMon looks powerful, but has almost no documentation.

Yep, not that much documentation. Just wanted to point out that the little documentation there is, is available at:



(9 replies, posted in Commodore Computers)

In most cases C64 Players execute once each screen update, so some standard C64 speeds are:

2 = 187.96703296703296 BPM
3 = 125.31135531135531 BPM
4 = 93.98351648351648 BPM
5 = 75.18681318681318 BPM

As Ilkke says, defMON allows you to set speed in a much more finegrained way that this. Nevertheless, you might still not hit exact "integer" BPMs like "125" etc. For example, by setting the timer interrupt value of the C64 in defMON to $4cf8 and using speed 3, you'll get 124.9997462572951 BPM, which is quite close to 125 BPM, but not exactly 125 BPM.

On the other hand, you can use Scannerboy's sync interface to make all your synths and gameboys and whatever obey the speed of the C64 running defMON. wink