OBI expander

[BJ]

BJ wrote:

 Paul Perry wrote:

 > At 01:29 AM 27/07/97 -0700, BJ from the land of home distilling
wrote:
 > ......some very relevant comments on PS's fantasies re Xpander
cloning......
 
> Ha,ha,ha,ha ,,, the land of home distilling. :-))
> You are 100% right paul perry.
> >From the middle and to the north of Sweden, Finland and Russia are the
> famous
> belt of home distilling,the danish pepole dont have this issue since
> they
> have a more liberate alcohol politic.And the norwegians just drilling
> after
> oil nowdays.
> 
> > the downside in my experience is the lumpiness of the control over the LFO -
> > the d to a convertor has not enough resolution at one end of the range - and
> > the unreliability of the whole thing (well, I have 2 of them and they are
> > both intermittent.....reseating the chips helps for a day or so ...... but i
> > don't fancy unsoldering the sockets then soldering the chips straight back in)
> 
 Do they use 8 bit or 12 bit of DA in the machine?
 I have seen about 4 different versions of the OBI knobi, one hade huge
 wooden sides.
 a early revision i think!

----------------------------------------------------------------------------------------
> Paul Schreiber wrote:

> > Yes, it was a 68B09 (which you can't even buy anymore!).
> >60% of the software is user interface: nothing to do
> >the sound at all.
 
 Why not using a 68HC11 or a 68HC12/16 series mcu, i think it
 would be much simplier then to migrate to a INTEL core?
 You could even use plenty of the old software and do some
 new subroutines?HC12 and HC16 are higer performance then
 68B09.
 One simple way is to over speed the 68B09.
 
 The 68B09 are not wery difficult to get here in europe
 they droling in every catalogue here!
 Why not use a higer speed MCU and do some adjustment in time
 parameters in the subrutine for the EG and LFO's.
 I belive a much more convinient way!
 
> 2) The rest was 6 LFOs, and 12 EG's, all in software.
> > Now THAT is a pain: I'm throwing chips at it!!
 
 Not that easy i think, you have to extend the mux channels
 by plenty.
 there is LOT of pains in software programing.
 
> 4) The design is clever, has alot of parts, but not THAT hard to do.
 Wath so clever about the design?
 
> > 5) But 1 display instead of 3.
> 1 display would limit the user interface i think?
 How many chips do you have to make ........numbers of complete OBI!
 
 I dont have any expirence of the OBI van knobi but thats one of the
 synths i regrett
 i didn't buing it back in 85.
 
 sorry for poor spelling.
 BJ in SAAB land......