Would it be possible to mod the RS7000?

[Hugo76]

I was at my friend's studio the other day where he demonstrated his old Yamaha TX16W sampler. It was known to have a terrible OS, but this was remedied by the Typhoon 2000 overhaul which made things much easier to understand. It also added some new features if I'm not mistaken.

So, I was wondering if this also could be done with the RS7000 synth/sampler/sequencer? Specifically, there is primarily *one* function I'm sorely missing, and that is loop crossfade. Maybe some improvements could be made to the synth as well?

What are your thoughts?

[meatballfulton]

Possible? Of course!

Will it happen? Only if some crazed RS fan does the work...much like the way Typhoon, JJOS and other third party OSes came about.

Are you volunteering?

[Hugo76]

Possible? Of course!

Will it happen? Only if some crazed RS fan does the work...much like the way Typhoon, JJOS and other third party OSes came about.

Are you volunteering?

Haha, unfortunately I don't have the programming skills for such a job. I was under the impression - or at least I assumed - that doing such a mod would require access to Yamaha technical sheets and whatnot. But how much work would a slight mod involve? Let's say implementing loop crossfade? We could perhaps do it as a team work, I volunteer to supply coffe and cookies!

[Zamise]

You can mod the RS, but the OS is off limits. Trust me, my love for the RS runs deep. I suppose you could try altering the hex code for simple hacks, but who knows what'll happen to your unit while your experimenting, unlikely any major overhaul would be possible doing it that way. I've taken a look at it, even tried to decompile the hex, but it seems to be an alien language. Also, Yamaha is not in the habit of releasing their code to anyone, least of all to their "bastard child" RS7000. I tried to negotiate purchasing the code, but long story short, the farthest you'll likely get is that someone at Yamaha will say they'll pass the request on to the higher ups, then you'll never hear from them about it. What we need is an insider, someone from the RS's original design team, and even then I wonder if the source is accessible, there is a good chance that Yamaha burned the code, lobotomized the designers and programmers and placed them in secret asylums across the country.

If you've not yet sign up to:

http://launch.groups.yahoo.com/group/RS7000/

We've been recently discussing mods such as SCSI drives, card readers, and even workaround for some cool sampling techniques that might do something similar to cross fading and multisampling, pitch zones, etc..

Zam

[ripe]

I have reverse engineered two different musical devices (Doepfer Schaltwerk OS and Yamaha AW4416 file format). It's not easy and in the case of an actual operating system for a realtime system like the RS7000, close to impossible for a normal human

I sold my RS, but in the case of the AW4416, it used a Hitachi SH-4 processor with an ITRON (µITRON RTOS) based operating system. This is a fairly Japanese centric OS used by industrial equipment, with very little hacking information available online. It's possible the RS uses something similar, but really for the time it would take to reverse engineer and rewrite the OS, you would be better spending the time developing something on the PC or finding hardware boxes that does what you want!

I did *not* reverse engineer the AW4416 OS, just the file system format. The Doepfer used a standard 8051 based processor so reverse engineering that OS was much easier than a Yamaha OS would be.

cheers
ripe

[Hugo76]

Damn, that's really too bad. I'm guessing Yamaha won't do another one like this again, so I'd really like to see it optimalised. In my view it's damn near a prefect box.
How did the Typhoon developers get access to the code? And the guys that made the jjos for Akai's mpc's?

[Alex E]

A couple years back I remember a site showing how someone built a nord micro modular into one.
Pretty crazy stuff.

(edit: here's the site http://sneak-thief.com/nordrs7000.html)

[Stab Frenzy]

How did the Typhoon developers get access to the code? And the guys that made the jjos for Akai's mpc's?

I heard the JJ crew were Akai developers that got fired and took the code with them and kept working on it.

[Hugo76]

I heard the JJ crew were Akai developers that got fired and took the code with them and kept working on it.

Really? Well, then we'd probably need some Yamaha guys - as Zam says - in order to get a mod going. What a bummer.

That Nord Micro Modular/RS7000 mod is awesome, btw!

ps: I'll join your site for further conspiring, Zamise!

[StepLogik]

If you could figure out the address space of the CPU then you would probably find it easier to just rewrite the OS from scratch rather than reverse-engineering what is already there. The problem is that there is probably a lot of Yamaha proprietary chips in the unit and unless you know the communications protocol those chips use, you'll have an extremely difficult time addressing them from the code and figuring what to do when they interrupt the CPU.

The Europa team reverse-engineered the Jupiter-6. Once they figured out the address space by looking at the schematics, they knew most of what they had to do without ever looking at the original source (although I recall they did have to refer to the original code quite a bit). That being said, the Jup's CPU wasn't addressing any proprietary chips or displays - it was just having to do the usual functions of a hybrid synth configuration.

Instead of trying to buy the source code from Yamaha, what you might want to do is see if they will give you the data sheets for any proprietary chips and the schematics of the machine. With that information, you could start rewriting the OS from scratch one feature at a time.

[Zamise]

I have the service manual, the CPU' is a HD6417709F80B part #XV250B00

What do I do next?

[StepLogik]

I have the service manual, the CPU' is a HD6417709F80B part #XV250B00

What do I do next?

Don't know anything about that other than the data sheet is available and there are development tools available.

Do you have schematics of the RS7000?

[masstronaut]

Seriously, just buy a sampler with loop crossfade.

[Zamise]

I have the service manual, the CPU' is a HD6417709F80B part #XV250B00

What do I do next?

Don't know anything about that other than the data sheet is available and there are development tools available.

Do you have schematics of the RS7000?

Yeah I could build one using the service manual, but coding an OS, I wouldn't know where to begin to do it. I think that may be why the source would come in very handy, that and 4 meg of raw code is a lot of typing and figuring from scratch. I figure the 4 meg they have as is, is pretty well optimized too. Part of the problem could very well be that, that is a barrier limit in itself, 4meg limit is also not a lot for an OS too, adding something may mean having to remove some other feature, and almost every feature on the RS is useful or pretty important or something I'd not want to lose on the RS.

I keep my hopes up, some day, some day I hope some programming electronic genius, probably autistic, will upgrade the memory and do it.

[StepLogik]

It would be incredibly challenging to work with the raw compiled code as stored in the unit's ROM. From that standpoint, it would be easier to write it from scratch! Based on reading the data sheet for that CPU, the code was probably written in C or C++, compiled, and burned to ROM. You will need to do the same.

As for adding features, it depends on the quality of the code and how much optimization the compiler did. One of the reasons the Europa team was able to add so many features to the JP-6 was because the existing code was so poorly written that they were able to optimize it and obtain more "room" for feature code. This is really not surprising - it was very common (and still is today in some cases) to let electrical engineers with little or no programming skill cobble together the firmware code. I've seen this numerous times in my professional career and it explains why a lot of devices have limited or buggy feature implementation.

This would be a fun project to "tinker" with. But, you might be better off just buying a new machine.