How do you do for .sid files into A8

[José Pereira]

Hi guys.

In Lemon64 and other C64 websites there's many of .sid files and there's lots of A8 conversions of them (like in ASAP).

I know that for musicians you may have other ways and/or resources but I was wondering if there is a simple way for a guy like me to take a .sid an then try some experimentals at RMT.

I also know that there is also that SidPlay but don't remember now if it's just playing what is already converted or it also can, in someway, import and convert .sid files (and I can't get it now because I'm at the streets and sorry but this is just another crazy idea I just had and 'shooted' it in here ).

 

So, my idea is to load a .sid file and in someway get it in such a way that I can load it into RMT.

Thanks.

[emkay]

Actually, there is no way to import SID into any RMT or other POKEY native format .

 

Well, it could all be easy: Use a full working Tracker on the PC, supporting all features of the A8 and POKEY, import the SID file, analyze the notations and Filter dependency and set POKEY values and timings, to get almost close as possible to the needed sounds for a dedicated tune.

 

As it seems, 37 Years after the 1st release of an A8 , the emulations get close enough to have all necessary on the PC. Well, the "Tracker" is still missing.

[Creature XL]

What I did...

 

You can use "siddump" to get a loooong list of all register changes (per VBI?) as a text file.

This you can parse and convert to anotehr text file which you can import in RMT.

Although you have to do it track by track. Its a lot of manual work.

I only did it for one track of "Midnight Resistance" to test my own player

 

Short: it is possible with manual work

 

EDIT:

I think tis is the program: http://csdb.dk/release/?id=18501

Just seeing that it is open source.

One can surely modify it to out put RMT-Tracklistings

Although I am more a fan of post-processing (the UNIX style, small tools working together instead of one big program)

Edited September 1, 2014 by Creature XL

[+JAC!]

The problem with both .SID and .SAP format is that they are actually no sound modules but plain executable files that can do anything.

 

In particular the .SID files does not have any module structure or knowledge thereof at all. For .SAP, at least a little information of the original file is retained, but you actually lost most of the possibilities of the original source file (CMC, RMT, DLT, TMC, TM8...) when you convert to .SAP.

 

In some cases, a qualified coder with proper hex editor may be able to re-extract a module from the .SAP, but it's far from trivial.

 

All of the above a reasons why I prefer the native formats over the .SAP format and I'd wished the

 

http://asma.atari.org/

 

archive would keep them whenever possible (as addition) instead of converting everything into .SAP. There are simply 2 use-case: .SAP for people who want to listen to the music (like .mp3) and .CMC/RMT/TMC ... for people who want to do something else with the music (change, use in code, transform...). Maybe I should write to PG, actually I assume he also has the native format somewhere back there archive would keep them whenever possible (as addition) instead of converting everything into .SAP.

 

There are simply 2 use-case:

- .SAP for people who want to listen to the music (like .mp3) and

- .CMC/RMT/TMC ... for people who want to do something else with the music (change, use in code, transform...)

 

Maybe I should write to PG, actually I assume he also has the native format somewhere back there.

Edited September 1, 2014 by JAC!

[emkay]

Actually, one reason to have "Sids" played on the A8 is they sound like SID.

Actually I have no idea to get closer to typical SID sound with RMT.

 

As differences in the timbre already change from emulation to emulation...

 

 

 

On the other Hand. If you want to play with available music files, there are converters from AY or YM to MOD , and then they could be imported into RMT.

Edited September 1, 2014 by emkay

[Rybags]

The "real" SID stuff on Atari is either with an actual SID chip or by software emulation.

 

You can take songs from C64 and get them working on Atari but it's not straightforward. SID chip on Atari lives at a different address than C64. Emulation works by allowing the tracker to execute with some of the CPU cycles while a timer IRQ emulates the SID chip with most of the remainder.

 

The less realistic emulation options either use 2 x 16-bit voices or translate SID notes to 8-bit values. So you either lose a voice or have much lesser note precision. And in both cases about the only waveforms are square or noise.

 

The other Atari music files you see around the place - either converted by someone by hand, or they were created in the first place alongside the C64 versions.

[sack-c0s]

I wrote a goatTracker editor file data extractor whilst I was trying to write a BBC music driver, but I don't know where it is these days. If I find it I'll throw it out there and someone could maybe look at re-encoding the data for RMT or some other editor

[emkay]

The less realistic emulation options either use 2 x 16-bit voices or translate SID notes to 8-bit values. So you either lose a voice or have much lesser note precision. And in both cases about the only waveforms are square or noise.

The solution for my example is still to have a correctly working tracker that is able to play the low notes per software ...

[Tezz]

Hi Jose, it's as Jac and Rybags have explained, the SID files are not a format as such but a C64 executable containing the player code and the data for the instruments, tracks, songs etc. There's a header added to the SID files for the various Sid play software which details the memory locations, # of songs, text info of the author, the year it was written etc. Many of the well known musicians wrote their own player procedures so they have their own structure and most revised them through the years. I've disassembled players from Rob Hubbard (who didn't revise his player for a long time), Jeroen Tel, David M. Hanlon and several others. The SID was designed for music and is a essentially a synthesizer controllable via it's hardware registers. It's not an issue of writing a software player for the A8 but as Rybags has mentioned above the main issue is that the SID is capable of 16-bit frequencies for all 3 channels. We have to combine two channels for 16-bit frequencies so we can only have two 16-bit channels at once. The procedures the Sweity wrote in emulating the SID via Pokey that I am making use of for Chimera is well thought out and cleverly interprets the SID register calls to swap Pokey channels and use a 16-bit frequency tables when possible on the fly. This works very well, I only had to transpose one pattern of the game completion song in Chimera as it was otherwise detuned with an 8-bit frequency table.

It should be possible to write a tool to extract the data from SIDs of a known player and build an RMT module if someone wanted to invest the time to do that but I think it's really best as a hands on task.

[emkay]

SIDs were no miracles. The running code is defined and the register values , and update speed, is also to get from a SID File.

The exisiting SID to MID tools tend to put every different note into another channel, instead of keeping the "3 voices" in a row. This in combination with fast transposing from note A2 to A7 (for example) , makes it useless to convert such a MID into MOD and then into RMT .

It's actually faster to write a piece of music yourself instead

Edited September 1, 2014 by emkay