Hi Hoschi
>>> Finding the correct MAC working with EII can be an adventure.
>>> current work I can see that the timing that EII provides on the
>>> serial port is beyond anything. It jumps like hell, making it
>>> currently impossible for me to connect any modern serial
>>> interface device to the EII
Good to hear that someone else is also having problems trying to
connect modern RS422 ports to the EII (see my experiments explained
on the emax group and on the eiiiforum).
Although in interactive mode I don't have any problems to "talk" with
the EII. And I also have software which can unload banks from the EII
to a PC within 20 seconds, although I have to admit that some re-
handshaking is required from time to time within the program loop,
which explains the difference between the 12 seconds on the Mac and
the 20 seconds on the PC.
I'm wondering though about this "jumping" argument... As far as I can
see the clock on the EII is pretty stable, and even if it's not, it's
also externally clocking the Mac so the impact shouldn't be that big
in terms of hardware syncing. So I assume you're not referring to the
actual clock but to the usage of the port by the EII software via the
Z80 ?
I'm still wondering why one Mac is "EII tolerant" while the other one
is not. The success rate seems not to depend on the Mac OS version,
not on the Mac processor speed, not on the Mac serial port circuits
(which are all the same and externally clockable), not on the amount
of RAM, not...
However switching from Appletalk ON to OFF can help sometimes, or the
other way around, and sometimes the printer port is OK, or sometimes
only the modem port, ... Really strange !
Anyway, we can e-mail offline to share further ideas about getting
this RS422 communication up & running with modern devices. I just
ordered my fourth RS422 PC port, so I hoping I made the right choice
now, either for the EII or the Emax or both :-)
///E-Synthesist
--- In emulatorII-list@yahoogroups.com, "hoschi1103" <totti@...>
wrote:
>
> All following information comes without warranty of any kind. It's
> late and I'm old. Get a second opinion :)
>
> IC132 is an MC1488, a 4x line driver for TTL to RS232. Pin 10 is
the B
> input of the 3rd driver. Cutting it will set DTR (Data Terminal
Ready)
> to be always HIGH. DTR is used on both RS232 and RS422 interfaces.
> SD will only connect if it detects the EII as a terminal on the
> serial. (Opposite a modem, which would set DSR (Data Set Ready).)
> I suppose that in early EII OS versions, this line was switched by
the
> EII in Macintosh mode but later they left it always on for a less
> troublesome connection.
> Please find a datasheet at
> http://www.klm-tech.com/technicothica/images/14881489.zip
> With the datasheet you can find and measure Pin 8, which should have
> +5V .. +15V immediately after you turn the EII on without a serial
> cable attached. If it is negative, the changes should be done to get
> the serial port working.
>
> R47 and R48 probably refer to the factory built in RS422 interface,
as
> the are not on the original schematics. Perhaps someone can have a
> look in their EII to confirm this. I suppose they are to be changed
> for a higher line voltage on the serial port.
>
> Finding the correct MAC working with EII can be an adventure. From
my
> current work I can see that the timing that EII provides on the
serial
> port is beyond anything. It jumps like hell, making it currently
> impossible for me to connect any modern serial interface device to
the
> EII. (I'm trying with different RS422-RS232 converters to spy the
> communication). This jumping is from the different length of Z80
code
> blocks used in the EII to handle all kind of in- and output. And
they
> do not really use interrupts as one would use them today :(
> So be glad if you can get a tolerant enough MAC that can handle
this.
> And never give it away.
>
> Greetings,
> Hoschi
>
> --- In emulatorII-list@yahoogroups.com, "jmp701" <jmp70@> wrote:
> >
> > Hi. I've spent some time recently getting my head around this
program
> > and soundbank transfers to EII etc. but to date have been unable
to
> > communicate with the E2 using the program installed on a Powerbook
> > 150. I know this isn't listed as compatible in the database so I
have
> > a Mac SE on the way which I hope to have more success with.
> >
> > However, after reading the Sound Designer troubleshooting manual,
I
> > may have another issue to resolve? The manual states that some
Rev 1's
> > have not had necessary modifications carried out at the factory,
> > specifically:
> >
> > 1. The trace leading to the end of R48 closest to the back panel
being
> > cut. This hasn't been done on my EII.
> >
> > 2. The trace going to lC132, pin 10 is to be cut (?) Whilst I can
> > see this chip to extract, how do I know which is Pin 10?
According to
> > the manual I have to bend this pin up and re-seat it, but I'm very
> > reluctant to cause damage when I'm not sure what I am doing.
> >
> > Can someone reassure me that I definately need to do both of these
> > measures (?) and how to identify pin 10 (which presumably leads
from
> > underneath the chip).
> >
> > For info I have a Rev 1 logic board with Version 2.1 EPROMS plus
OS
> > 2.3 and 3.1 disks for use in the EII. I've also ensured MIDI is
on in
> > OMNI mode with no MIDI cable attached.
> >
> > Thanks for any help you can provide.
> >
>