Emax

Thanks for sharing the Emax-2 MIDI and RS422 specs !
This kind of documents is so hard to find.
I've downloaded it right away :-)

Regarding your question about progress on the RS422 device:
there has been a lot of silence indeed, but I hope to receive a test device very soon in my postal mail box. This particular device seems to have run my test program successfully, so I hope I can even make it actually load/unload banks between a PC and the Emax (and even EII !!)

///E-Synthesist
--- In emax@yahoogroups.com, Tristan <tu@...> wrote:
>
> Has there been any progress with the USB to synchronous RS-422
> interface?
> 
> My work on the synchronous RS-422 to asynchronous RS-422 converter ran
> aground when I found the microcontroller was unable to handle the
> number of interrupts generated by bidirectional communication at 500k
> baud. The interface also needs to handle the baud rate switching on
> the Emax side itself by either monitoring the transfer protocol or by
> receiving some non-Emax sysex messages from the PC host.
> 
> The potential issues with either of these options mean extensive
> debugging and ongoing upgrades to firmware would probably be required.
> However, I believe it would be possible for the host PC side to use an
> RS-232 port with auto baud rate setting, so it could potentially work
> with any USB to RS-232 or built in RS-232 interface. Anyway, to move
> forward I will need to upgrade to a faster microcontroller which will
> also allow for in circuit flash upgrade of firmware. But if the USB
> alternative is already working then there may not be too much point.
> 
> I found a copy of the Emax 2 MIDI and RS-422 specifications which I
> have scanned and uploaded to the files section. It details the 12 bit
> and 16 bit high speed sample transfer protocols as well as the Emax
> bank image transfer protocol. It appears the Emax 2 was designed to be
> compatible with the RS-422 CDROM drive after all! It also explains
> differences between the implementations on the Emax and Emax 2 as well
> as some Emax 2 bugs and corrections in various OS revisions. I also
> have hardware information on the Macintosh serial interface that the
> Emax is designed to interface with, but I have not uploaded it yet.
> 
> /Tristan
>