Emax

Hi Mike, 

An old Mac with Alchemy or SoundDesigner for Emax is not an option, 
since the whole point of my project is to "port" the communication 
features to the Windows platform (as part of EMXP) :-)
Of course I have some Macs with Emax/Emulator software and it works 
great. I also need this setup for reverse engineering purposes. But 
once I would be able to communicate directly between the Emax and 
EMXP, I could add some features which are not available in any Mac 
software. E.g. sending/receiving full banks at once.
In fact this feature could be a nice alternative for people having an 
Emax rev1 version. The other Emax versions can be upgraded with SCSI 
which is probably even more interesting than a computer based bank 
unload/load...
Until now I only tested Windows RS422 communication with the Emulator 
II. But maybe I should also do some tests with the Emax... if I'm 
lucky the receiver chip circuit of the Emax is more "friendly" than 
the one of the EII.
We'll see...


///E-Synthesist

--- In emax@yahoogroups.com, Mike Wolak <mikewolak@...> wrote:
>
> Have you considered just using an old Mac with Alchemy 3.0? I do 
this quite reliably for sample dumps between my EMAX and Mac 9600 and 
the cost of an old Mac is most likely less than a USB->RS422 
converter.
> 
> 
> 
> 
> --- On Mon, 10/27/08, esynthesist <esynthesist@...> wrote:
> 
> > From: esynthesist <esynthesist@...>
> > Subject: [emax] Re: Emax SCSI Upgrade kits - WARNING...POSSIBLE 
RANT
> > To: emax@yahoogroups.com
> > Date: Monday, October 27, 2008, 4:41 PM
> > OK, other members seem to confirm that the additional 4
> > holes are on 
> > the PCB already :-)
> > 
> > About my RS422 experiments: in fact I'm able to
> > communicate with the 
> > EII, it's just that the communication is a little bit
> > unreliable when 
> > receiving data from the EII, and *very* unreliable when
> > transmitting 
> > data to the EII. In my opinion the only two possible causes
> > can be:
> > - problem in voltage level
> > - problem with timings.
> > Since receiving data goes quite well (18-20 seconds
> > including re-
> > handshakes compared to the 11 seconds without re-handshakes
> > on a Mac) 
> > I don't think there are timing problems. Both the EII
> > port and the 
> > USB/RS422 converter are clocked at 500kbaud - note I had to
> > buy a 
> > specific USB/RS422 converter since the standard ones are
> > not capable 
> > of being clocked at 500kbaud. But still this is a different
> > situation 
> > compared with the Mac since the Mac's serial port is
> > externally 
> > clocked by the EII's clock, which guarantees of course
> > that they are 
> > synced. This external clocking is simply not available on
> > RS422 PC 
> > ports.
> > My guess however is that the USB/RS422 transmit signal is
> > too low for 
> > the EII (or more particularly: the differential transmit
> > level is too 
> > low). I'm pretty convinced about this because
> > "getting a bank from 
> > EII" goes very well while "sending a bank to
> > EII" is a disaster. 
> > Sending data from PC to EII requires of course a lot more
> > bytes to be 
> > sent than receiving data, and my experiments show that the
> > stream of 
> > data seems to be partly "destroyed" when it
> > arrives at the EII (the 
> > EII answers with a NACK or keeps waiting for more data
> > because it 
> > thinks not all data have been received yet).
> > However I don't have a digital scope to confirm this...
> > but I'm 
> > really thinking about buying one now ! Now even when the
> > scope 
> > confirms my thoughts, the next question is what I should do
> > to solve 
> > the problem. Building custom hardware seems not very
> > attractive from 
> > the perspective of potential EII users I guess...
> > 
> > Mmmm... interesting but frustrating... just like upgrading
> > the Emax 
> > with SCSI :-)
> > 
> > PS: I'm still waiting for a reply from my synth repair
> > guy concerning 
> > the SCSI upgrade.
> > 
> > ///E-Synthesist
> > 
> > 
> > 
> > 
> > --- In emax@yahoogroups.com, Ted Summers <djtbs1@>
> > wrote:
> > >
> > > Thanks for the encouragement.  From my understanding,
> > the holes 
> > are  
> > > already there for the socket.....
> > > 
> > >  >> In fact I think this expense problem is part
> > of and compensated 
> > by
> > > the challenge/kick/hobby/appreciation...isn't it ?
> > > True.....
> > > 
> > > On your project---
> > > 
> > > Regarding the USB converters- are you working on Mac
> > or Laptop 
> > that  
> > > has no serial? The serial is RS422, at 500kilobits
> > (not bytes) per  
> > > second, according to the service manual. it also says
> > the RS422 is  
> > > using differential mode.
> > > Here is a web page discussing that:
> > > http://www.lammertbies.nl/comm/info/RS-422.html
> > > 
> > > Maybe you already know about these things, but just in
> > case.....
> > > 
> > > I would think the biggest challenge there would be
> > timing between 
> > USB  
> > > and the RS422, and I believe RS422 uses different
> > signal levels. 
> > It  
> > > may be that the USB is using too low of signal
> > levels....
> > > 
> > > just a couple of thoughts.
> > > 
> > > Regards,
> > > Ted
> > > 
> > > 
> > > 
> > > On Oct 25, 2008, at 9:36 AM, esynthesist wrote:
> > > 
> > > I think quite some Emax users really appreciate your
> > efforts !
> > > 
> > > So do I, and I didn't even buy your SCSI kit (yet)
> > :-)
> > > 
> > > In fact I was very enthusiastic when I read about your
> > SCSI kit and 
> > I
> > > was even more thrilled when I discovered my Emax SE
> > keyboard had a
> > > Rev2 board.
> > > But... my enthusiasm kind of disappeared when I
> > started reading the
> > > SCSI Upgrade instructions. My headache reached a
> > climax when I read
> > > that a 24-pin IC socket should be removed and replaced
> > by an 28-pin
> > > socket (what about the PCB holes for the 4 additional
> > sockets ??)
> > > So as other members already mentioned: the problem is
> > probably not
> > > the price (which is really fair) but the technological
> > challenge and
> > > the risk to destroy a perfectly working Emax.
> > > Personally I'm thinking about outsourcing this
> > upgrade job to my
> > > synth repair guy but I have to ask him a price
> > estimation first.
> > > 
> > > Of course this kind of upgrade/rev.engineering
> > activities take a lot
> > > of time and may also require some "personal
> > cash" investment.
> > > E.g. for developing EMXP and making sure everything
> > works fine I had
> > > to do quite some investments. At the beginning I
> > thought that having
> > > an EMAX SE, an EMAX-II, an EII+, and an EIIIXS would
> > be sufficient
> > > for making sure that the software works on all
> > samplers of those Emu
> > > families.
> > > But it seemed I had to buy an Emax Plus and a
> > "real" EIII also,
> > > machines I didn't need otherwise. Especially the
> > EIII was very
> > > expensive and I'm still not really using it -
> > it's just sitting 
> > there
> > > for test purposes of EMXP. (true, I can sell them
> > again when I stop
> > > developing this software)
> > > Another example: for the past few weeks I was trying
> > to add serial
> > > communication to EMXP for the Emax and EII. But to
> > come to the
> > > conclusion that this will probably not be possible, I
> > first had to
> > > buy two USB-RS422 converters and one USB-RS232
> > converter.
> > > I'm glad I didn't buy a 1000+ EUR digital
> > oscilloscope yet :-)
> > > 
> > > But I don't really care about these expenses,
> > fortunately I don't
> > > have a wife :-)
> > > In fact I think this expense problem is part of and
> > compensated by
> > > the challenge/kick/hobby/appreciation...isn't it ?
> > > The fact that we are helping some Emu fans out there
> > and that they
> > > really appreciate our efforts could be our main
> > driver/objective.
> > > 
> > > Many thanks for the efforts and I'll probably send
> > you an order in
> > > the coming days/weeks !
> > > 
> > > ///E-Synthesist
> > > 
> > > --- In emax@yahoogroups.com, "Ted Summers"
> > <djtbs1@> wrote:
> > >  >
> > >  > Thanks for your words of encouragement. $2500-
> > wow. My wife 
> > freaked
> > > when she
> > >  > realized I had spent the $900 (although she
> > somewhat chilled out
> > > when I told
> > >  > her that I had made some of it back)---- I
> > couldn't imagine the
> > > amount of
> > >  > your project .... I hope people start coming
> > through for you as
> > > well.
> > >  >
> > >  > It is all very easy for people to say it could
> > be done cheaper. I
> > > think we
> > >  > both know it isn't all as easy as it sounds.
> > You never really 
> > know
> > > what it
> > >  > is gonna take until you get into it. And once
> > you get into it, 
> > you
> > > feel like
> > >  > you wasted your money / time if you just drop
> > your effort too....
> > > catch 22.
> > >  >
> > >  > Best of Luck!
> > >  >
> > >  > Regards,
> > >  > Ted
> > >  >
> > >  >
> > >  > [Non-text portions of this message have been
> > removed]
> > >  >
> > > 
> > > 
> > > 
> > > 
> > > 
> > > 
> > > [Non-text portions of this message have been removed]
> > >
>