Early serial EII w/RS422upgrade board but no comunnication to mac...help?

[AnaRenaissance1]

Hi guys! This is my 1st post! as i'm a new emulator II user This forum as been invaluable so far so thanks to all the members! Here's whats up!

I have two probs: 1st, I cannot get my Emulator 2 to connect to sd4EII on an old Mac SE. 'I can't communicate with the E2! Make sure cable is connected and the current preset has MIDI on' is what is says. 2nd, i cannot find a 4.2 zip driver so that i can use my zip drive with the mac to transfer my soundbanks over...

Here's what i'm working with:

1x EmulatorII (serial 831) software 3.1
1X Mac SE running system 6.0.7
1x Custom made cable from Rob at emulator archive
1x floppy disk of Sound designer for EII (installed on mac successfully)
1x 100mb iomega zip drive w/scsi cable
+ big sound library on disks and on CD as SD format etc.

After taking lid of my emulator (and simultaneously fixing the dropout of voices 2 and 3 i found i have the following (i'll post some pics)

*Output revision board on left under power supply =REV 1(15may 1984)
*Emulator 2 memory option board =Rev 0, (30 april 1984)
*Main board on right underneath memory option board is = rev 0 10 april 1984 with serial 789.
*E2 Mac int (bd rev 1985) which is connected to the computer interface. i believe this small board to be the upgrade for early E2s to comunicate with macs Phew!. (IC1 and IC2 are intact but IC132 (cn2) and IC108 (cn1) are not there)

I have read the other post/s on this topic, and tried the suggestions..appletalk on/off.midi set to omni but still no joy.. any further help/suggestions would be greatly appreciated.

Thank you all in advance..

Miles

P.S Also if there any EII users on the forum based in London, UK that may let try a few different configurations to see where my problem lies.. lunch is on me!

[AnaRenaissance1]

I'd like like to add that i've just tried putting the EII into 'mac mode' as per another thread, using the special functions 16 on the EII.  'Under the control of MacIntosh' appears on the EII screen but there is still no communication between SD and the EII... The EII is then stuck (crashes) with that message on the screen and the a reboot is necessary for it to function again.
I am using the modem input on the back of the Mac SE....

Can any exist users of SD with EII give me a little summary of what they do when the start up using SD with EII i.e which is powered on 1st, any import setting necessary for the connection to be made etc

Thanks again

[esynthesist]

Do you have a voltage meter (multi meter) or - even better - a (digital) oscilloscope ?
There's a chance that either the receiver or the driver IC of that upgrade board is dead.
Perhaps you can measure the voltages on the DB25 connector pins (pins 2, 3, 9, 10 an 11) ?

[AnaRenaissance1]

Hey Esynthesist, Thanks for your reply and the pm! I do have a multimeter although i'm not that sure how to use it if i'm being honest! i'll find out how to test the voltage on the Pins and i'll post up my findings! Are there some correct voltage read outs that i should be expecting..? how will i then be able to tell whether it's the receiver or the driver ic that is dead?

Thanks again for your help

Miles

[AnaRenaissance1]

Wow.. my last reply was over 5 years ago! 

The world has changed some but... I fortunately still have my E2 and I'm finally putting time aside again to look into this mac communication issue again. I've gained a lot more technical knowledge over the last few years repairing/ building a variety of studio kit. I'll continue adding my progress to this thread incase anyone else finds it helpful.

The voltages i currently have on the DB25 are:

Pin 2: - Receive 0.72v ( according to Rs422spec doc this should be close to -4v)
Pin 3: - Transmit 0.23v
Pin 7: Sig Gnd 0.08
Pin 9: 500khz 0.08
Pin 10: + Receive 4.24v
Pin 11: + Transmit 3.77v

I've bought and replaced the RS422 line driver and receiver chips on the small mac upgrade board.

These readings are with mac not connected to the E2. Im going to hunt down the cable and connect the mac and see what happens...

[AnaRenaissance1]

So i connected the Mac SE and tested the voltages on the DB25 computer interface of EII and it seems they're off...

Readings:

Pin 2: 1.27v
Pin 3: -0.82v
Pin 7: 0.07v
Pin 9: -4.62v
Pin10: 3.54v
Pin 11: 4.52v

The readings according to the EMU RS422 Document say they should be:

Pin #
2
-Receive Data
Nominal ± 4V
Absolute maximum ±15V
EII Input

3
-Transmit Data
0 to 4 V
EII Output

7
Signal Ground
Ground

9
500 kHz Clock
-1.5 V to +2.5 V
Ell Output

10
+Receive Data
Nominal ± 4V
Absolute maximum ±15V
Ell Input

11
+Transmit Data
0 to 4 V
Ell Output


The readings on the receive pins 2 and 10 don't change when any commands are made from the mac. On the output of the E2 a little short 'clip' sound is made when i make any command on the mac.

I'm wondering whether cable is wired correctly (should be, its from Rob at Emu Archive), whether the rs422 drivers on the small mac board are functioning correctly (blown again?), whether the issue needs to be traced further back onto the digi board or whether i need to try another mac. I would like to get some correct readings before determining that the mac needs to be changed..

Gonna carry on tomorrow,

Any pointers appreciated.

Thanks

[razo]

Hi, I have exactly the same symptoms on my EII..
You must measure the voltages on the DB-25pins without the mac connected to be able to compare with the reference values.