E-mu Emulator Sampler User Forum for the EIII EII EI and EIII XP - EIII Memory controller RAM

Welcome, Guest. Please login or register.
Did you miss your activation email?
October 18, 2017, 02:22:30 AM
Home Help Search Login Register
News: Want to register? Then please don't use a Hotmail, Yahoo or Gmail address. They'll block the activation email.
Still having problems activating your account? Send an email to: EIII @ telenet.be

+  E-mu Emulator Sampler User Forum for the EIII EII EI and EIII XP
|-+  General Category
| |-+  EIII Technical Issues / Tips
| | |-+  EIII Memory controller RAM
« previous next »
Pages: [1] Print
Author Topic: EIII Memory controller RAM  (Read 2323 times)
Freddy
Full Member
***
Offline Offline

Posts: 91


« on: February 09, 2014, 06:32:51 PM »

Hi  Wink

As I just finished repairing my EIII rack and hence I'm in the lucky position to swap parts and board in between my faulty EIII keyboard and my working EIII rack. I spotted a lot of things that I learned from my EIII rack repair.

- faulty EIII keyboard: 8MB RAM Firmware 1.00 OS 2.42
- working EIII rack: 8MB RAM Firmware 2.00 OS 2.42

As the firmware of the keyboard is just 1.00 and the OS floppy is 2.42 of course it doesn't boot, but for testing purposes I swapped the firmware chips and it works. I'm currently trying to update them... but that's a different aspect now.

This is probably hard to imagine, but maybe you can help me getting 4MB RAM on my keyboard back  Cheesy

In order to check if the CPU board of the faulty EIII keyboard is fine (Firmware chips 2.00 taken from the rack CPU board), I put it in the EIII rack (8MB) and it boots... Wait, what's that?! Why does it only display 4 megs?
Subsequently I had a look at the upgrade manual and this confirmed my suspicion.
The memory PALs are on the memory board.

From this I conclude that the CPU board also contains a kind of PAL that handles the memory.

Does anyone of you know which PAL(?) that is?
I wasn't able to find a hint in the service manual

Thank you!
Logged
Freddy
Full Member
***
Offline Offline

Posts: 91


« Reply #1 on: February 24, 2014, 04:47:50 PM »

I found out it's a broken PAL on the microcontroller board labelled "PAL16L8ACN" on IC27 (IP374 or E3 CS PAL in the service manual). I swapped it with the equivalent from my working rack which makes it 8MB. As far as I understand it's a custom chip made for emu Sad
...
Logged
Freddy
Full Member
***
Offline Offline

Posts: 91


« Reply #2 on: March 04, 2014, 08:46:15 AM »

On a german micro-electronics forum I started a thread and got many reactions. A guy who collects vintage PCs helped me and finally was able to copy the PAL (which can only be written once) to three GALs (rewritable). Seems to be really complex. He said the chip was write-protected so had to perform some kind of reverse engineering using some old PCs and DOS programs to solve tons of equations ... I really didn't understand what he tried to explain to me  Cheesy
But obviously EVERY PAL can be copied this way.

He sent me 3 copies and they all work. I will keep one spare chip, but I still have one that I'm willing to sell for a few euros. So if you have 8MBs and the PALs installed, but still only get 4MB have a look at IC27.

I attached 3 files which he sent me and obviously contain the necessary data, just in case you can burn PALs on your own.

Note that this file does not seem to be the one you need to upgrade the EIII from 4 to 8MB. According to the upgrade PDF you only have to change 2 PALs on the memory board. I don't know what exactly IC27 (on the CPU board) is good for (does anyone know it?), but for some reason I had a version that only allowed 4MB to be used which I now upgraded.

* EMU3_8M.HEX (5.65 KB - downloaded 112 times.)
* EMU3_8M.JED (23.42 KB - downloaded 113 times.)
* EMU3_8M.PLD (25.09 KB - downloaded 109 times.)
« Last Edit: April 17, 2017, 06:21:19 AM by Freddy » Logged
wirefall
Full Member
***
Offline Offline

Posts: 39


« Reply #3 on: March 04, 2014, 11:47:23 AM »

Thanks for the binaries, great to have them!  Smiley

I really hope somebody could find that PAL which offers the upgrade of 16 MB RAM. If I got it right, this was announced by Emu, but never released (see posting about this somewhere here in this forum).

As your helping guy seems to be an expert: Could he find out how a PAL must be programmed to offer 16 MB? If he could find out for shure I owe him some crates of Franziskaner!  Grin
Logged
Freddy
Full Member
***
Offline Offline

Posts: 91


« Reply #4 on: March 04, 2014, 02:44:19 PM »

That's a good and I just sent him an e-mail ..

Original answer in german:

"[...] Der Soundprozessor stellt den SIMMs zehn Adressleitungen bereit, d.h. Du
kannst maximal 1MB pro Slot bestücken. Davon gibt es 16 Stück, von daher
sollte die Hardware 16MB ansprechen können. Wahrscheinlich müssen dann
I27, I47 und I50 angepasst werden. Die spannende Frage ist aber, ob die
Software dann was damit anfangen kann, oder ob das Betriebssystem
trotzdem nur 8MB nutzt. Das anzupassen dürfte nicht einfach sein --
schon alleine wegen der Seltenheit des verwendeten Prozessortyps.
"

Fast english translation:

"The sound processor provides the SIMMs with ten address lines, which means that 1 MB per slot is the maximum. Now there are 16 slots and for that reason 16 MB should be possible when it comes to the hardware. Most likely IC27, IC47 and IC50 have to be modified. The exciting question will be if the operating software can handle more than 8MB. And to make the software work with 16MB will be the most difficult point especially because of the rarity of the used processor."  Smiley

I think technically this guy (doctor of engineering, works at a university) should be able to do it and says if he finds the time he's willing to help me, I really appreciate his time and efforts...

Is there anyone around here (esynthesist?) who has a deeper insight into the software or do you know someone who has that? Even if you only have a link..
Logged
dvdborn
Administrator
Full Member
*****
Offline Offline

Posts: 236



WWW
« Reply #5 on: March 04, 2014, 04:02:40 PM »

This is great news. I always was under the impression that the PAL chips couldn't be copied.
Thanks for sharing these binaries!
Logged
smokie
Jr. Member
**
Offline Offline

Posts: 11


« Reply #6 on: March 07, 2014, 09:25:48 PM »

That is awesome that we might be able to get 16 meg. At the very least it will help to keep are samplers working in the event of pal chip failure.
Logged
Freddy
Full Member
***
Offline Offline

Posts: 91


« Reply #7 on: March 08, 2014, 12:12:30 PM »

Hi,

1) the good news are, yes don't worry about the PALs. Even the dedicated memory PALs (8MB) can be easily copied by a professional.

2) The (really) bad news are. The memory upgrade is absolutely impossible. I found a german doctor of electronics who is interested in synths and did perform some really cool upgrades on other vintage synths. This guy is even more specialized on microelectronics and computer architecture than the first one I found.

He says this must have been a big myth in the E-mu Community and that E-mu surely never considered it as an easy upgrade. His e-mail was a pure devastation of the idea. Overall it would take months and thousands of euros if I would pay an electro engineer. Not only that the software has to be rebuild, but also the hardware.

Well the e-mail comprises 3 pages employing a pretty technical and colloquial german why it wouldn't work and what had to be done. Please understand that I won't translate everything, I edited it extensively so that google translator won't translate rubbish and attached it as a PDF. You might understand most things via google translator.
Black was my message, blue his answer, green quotes from the first technician I contacted and orange a message from an electronics forum.

Would have been too cool. However 8MB are also acceptable and forces you too be creative  Wink

* EIII RAM Upgrade E-Mail.pdf (63.17 KB - downloaded 127 times.)
« Last Edit: May 19, 2014, 01:39:51 PM by Freddy » Logged
rectape
Jr. Member
**
Offline Offline

Posts: 29


« Reply #8 on: February 26, 2017, 12:01:04 PM »

Hi guys,

I've just received my eiii rack but it seems to be a 4meg version.

Someone can help me to max it out to 8meg or is it too difficult?

Thanks.
Logged
dr.c
E-mu Doctor
Hero Member
*****
Offline Offline

Posts: 903


I'm a hot dog !


« Reply #9 on: February 27, 2017, 05:12:31 PM »

The PALS can be copied, I did it many times !
Logged
Pages: [1] Print 
« previous next »
Jump to:  


Login with username, password and session length

E-mu Emulator Sampler User Forum for the EIII EII EI and EIII XP - EIII Memory controller RAM

SEO light theme by © Mustang forums. Powered by SMF 1.1.21 | SMF © 2015, Simple Machines