Emax

Doesn't anyone ever check the archives, if you do a search you will find all the info on this, but just for the record-
It does work.
-You need an emax with the expansion board.
-If the emax has 2 meg on the motherboard, you can expand it to 8 megs
-If the emax has 1 meg on the motherboard, you can expand it to 7 megs
-The pals are different on the expansion boards, so you can't use a  board from a 1 meg machine in a 2 meg machine (or vice-versa)
-You need to remove the 93C06 eeprom from the motherboard, be very careful it's a 4 layer board, the best is to snip it out, then desolder each pin.
-Solder in an IC socket, reprogram a new 93C06, plug it in, populate the board with ram, and your good to go.
-Do not turn on the machine with the 8 meg eeprom unless you physically have 8 megs of ram, otherwise you will loose the data in the eeprom, and have to reprogram it.
The 8 meg file for the eeprom is in the files section.

Dave





--- In emax@yahoogroups.com, "Simon" <chevytravelleruk@...> wrote:
>
> I guess the first stage of testing would be if I could transplant my known working 8Meg exp board into one of my other Emaxes and then replace the EPROM and see if it sees all 8meg.
> Once we know the prom works, then work on populating a 4meg board and go from there
> 
> I'm away from Sunday until 16th but then I'll dive in to my Turbo Emax and take pictures.
> Do you have the EPROM image Richard?..
> 
> 
> Simon
> 
> 
> --- In emax@yahoogroups.com, Rish <rish@> wrote:
> >
> > I have the EPROM burner and will burn EPROMs for this project for free until we figure it out and after that I would charge a small fee.
> > 
> > Also it is my experience that not all chips that EMU said were PALS actually are really PALs. They did this to protect their proprietary hardware, this was a common practice with EMU and many others.
> > 
> > Richard 
> > 
> > Sent from my iPod
> > 
> > On Nov 26, 2010, at 9:03 AM, "Simon" <chevytravelleruk@> wrote:
> > 
> > > Wow.. interesting and informative Ted.. I have an 8Mb Emax and a couple of 4 meg machines.. I'd be quite interested in trying them to see if that trick could work. Is there any particular EPROM reader/writer you'd recommend for this or is one much the same as another?..
> > > Also.. would there be any way of duplicating/imaging the install discs, assuming we could find one
> > > 
> > > Simon
> > > 
> > > --- In emax@yahoogroups.com, Ted Summers <djtbs1@> wrote:
> > > >
> > > > That is if you have 1MB RAM- if you have 2MB it may be possible to update it
> > > > someway.
> > > > Although my efforts were not successful.
> > > > 
> > > > I had 2 units- 1 with 1MB and one that is an 8MB.
> > > > Taking the 8MB board, I was not able to take an copy of the 8MB EPROM and
> > > > the board and just move it over.
> > > > It didn't work.
> > > > 
> > > > Regards,
> > > > Ted
> > > > 
> > > > 
> > > > On Wed, Nov 24, 2010 at 8:07 AM, Ted Summers <djtbs1@> wrote:
> > > > 
> > > > > The issue isn't the circuit- schematics are available.
> > > > > The issue is that:
> > > > > 1) The upgrade disks are not available.
> > > > > 2) The upgrade requires registered PALs.
> > > > >
> > > > > So- for number #1 it may be possible to write / copy an eeprom to update
> > > > > your memory.
> > > > > Someone on the group says they did it, but I could not replicate their
> > > > > effort.
> > > > >
> > > > > 2) You cannot read registered PALs.
> > > > > So if you don't have the original binary (we don't), then you can't make
> > > > > duplicates of them.
> > > > >
> > > > > Currently there is only 1 way to break a registered PAL- reverse engineer
> > > > > it using an high power (electron?) microscope to see each switch gate and
> > > > > map it out.
> > > > > The cost to have someone do that is very prohibitive, and may even be
> > > > > illegal in some countries.
> > > > >
> > > > > There is a team / person I have contacted that is working on a piece of
> > > > > equipment to read / determine registered PAL programming, but he is sometime
> > > > > away from a usable prototype for Registered PALs. The equipment is likely to
> > > > > cost about $300 when it becomes available..
> > > > >
> > > > > That is as much as getting a working Emax2 with memory off ebay....
> > > > >
> > > > > Regards,
> > > > > Ted
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > > On Wed, Nov 24, 2010 at 4:14 AM, Niklas N <niklas627@> wrote:
> > > > >
> > > > >>
> > > > >>
> > > > >>
> > > > >> Have a few questions about memory for Emax 2
> > > > >>
> > > > >> - Does anyone know where I can get memory to Emax 2?
> > > > >> - Is there anyone who has tried to "build" memories or have a schematic
> > > > >> sketch of the memory? The circuit is quite big, so it should not be
> > > > >> difficult to build if you have knowledge of how to build a circuits.
> > > > >> Maybe someone can post a picture of how the circuit looks like and what
> > > > >> components are on it? Maybe can I make a sketch from some pictures.
> > > > >> - Is upgrade disks to memory to obtain or can someone post this on
> > > > >> formumet so you can download it in the EMX format?
> > > > >>
> > > > >> cheers
> > > > >> niklas
> > > > >> www.myspace.com/non73audio <http://www.myspace.com/non73audio>
> > > > >>
> > > > >> [Non-text portions of this message have been removed]
> > > > >>
> > > > >> 
> > > > >>
> > > > >
> > > > >
> > > > 
> > > > 
> > > > [Non-text portions of this message have been removed]
> > > >
> > > 
> > > 
> > 
> > 
> > [Non-text portions of this message have been removed]
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