Coincidental that this obscure topic should come up! I happen to
have an X-Calibur board. The other day I was reading the readme file
on the driver disk that came with the X-Calibur and it gave me an
idea. According to the doc, the X-Calibur is "designed to be fully
upward compatible with the 'soon to be released' 68060 processor from
Motorolla". That got me thinking. Hmmm.. Does that mean the X-
Calibur could (in theory at least) ride atop, say, a CyberstormPPC
card?? Just out of curiosity I checked the orientation of the chips
on the two boards and how this might be done. And you know what?
They line up *almost* perfectly! I say almost because the X-Calibur
would barely clear the PPC with a small heatsink, leaving no room for
a fan. A platine or riser of some sort would have to be built to
raise the X-Calibur enough so that the PPC could breathe. The other
issue(s) I can forsee would be to make sure the X-Calibur does not
feed the 68060 +5V. Power would have to be converted to +3.3V for
the 060. The memory on the X-Calibur (4x72 pin SIMM 32M/each) should
be easily addressable by the Cyberstorm, right? Same as if I had a
DKB3128 plugged into a Zorro slot. Also, the BlizzardPPC can address
256Meg so I see no reason why the Cyberstorm couldn't. It sounds
kind of crazy but after considering this a bit, I actually believe
this could work. Comments/feedback/assertions of insanity are more
than welcome on my idea.



--- In Amigacoldfire@yahoogroups.com, "Oliver Day" <oliver@...> wrote:
>
> Hi
>
> > I wonder if it would be very complex to create a board similar
> > to the old X-Calibur board for A3640, that plugged between the
040
> > and the A3640 and contained 128MB (soldered).
> > There are thousands of A3640 boards out there that are almost
> > useless because you can't fit more than 16MB in the motherboard.
>
> Could it be done, yeah. Xilinx give the code away for Dram and
SDRam
> controllers for use with their CPLD's, but honestly it aint worth
it
> imho. (unless a cheap adaptor for the A2000/A500 could be made that
> would use the low end fast slot cards, which you could maybe build
> the memory controller on too)
>
> > I guess that with a small FPGA that acted as memory controller
> > for the 040 and a pair of 64MB DDR memory chips it would be
enough.
> Argh DDR, noooooo.
> Come on, 72 pin simms are easy to add, there are the designs on
> aminet for adding 8 meg of ram to an A500, the design would only
need
> a minor change to fit directly on an 040 bus.
> SD-Ram would be ok too, but nooooooo not ddr. :) (yeah I know you
> will come back with "but you cant get simms and sdram any more", I
> just ordered 128meg of brand new 72pin simms (60ns) and it cost me
> £20, every computer shop in the UK seems to still stock 72pin
simms,
> even the one up the road from me)
>
> A new 68060 card would be much better and with the price of PCB's
and
> CPLD's/FGA's falling all the time you could probably make a very
> cheap 060 card, the fast slot connector would be the biggest
expense.
> Even second-hand 060's are cheap from ebay. (And there are ways
round
> the rohs system so you could sell a new 060 card thats rohs
compliant
> and just have a plug in second hand 060 chip)
> Anyway thats going off topic rather fast.
>
> The answer is yes it can be done, the code is availble for some
> generic memory controllers like as you say opencores and xilinx.
> I have no idea what the price would be like, say £55-ish retail
maybe.
>