emulatorII-list

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.
>