Date : Sat, 04 Mar 2006 22:58:00 +0000
From : mogwai <fragula@...>
Subject: Re: Warning: Sad case on list!
Howdy John!
John Kortink wrote:
> I have one of Sprow's ARM 2p, highly recommended, an
> excellent development.
Indeed. I'm giving it very carefull consideration. Have to see if I have
an available universal cheese wedge too. It looks a great box.
> There's also the 'impure' GoMMC, the perhaps perfect
> companion to the ARM 2p. And probably more impurity
> to be found in backwaters on the net.
Oh my yes.. You've used one of those? Its memory footprint is just the
same as a 27128 yes? No flying wires?
> For speed, yes. Simplicity hardly. A 6502 core is large
> and putting one in the FPGA is hardly a trivial task. To
> say nothing of putting in others.
A 6502 core (actually a couple of them) are floating around open source.
No Comment on the quality - I aint tried them.. However I meant from the
point of view of flexibility. A JTAG cable (preferably from an on-board
interface or maybe a 1MHz bus device) and, admittedly a fairly extended
break-from-keyboard and you could swap between 6502 2MHz, 3MHz, 250MHz,
Z80, x86, 32016 (as if anyone could be arsed doing it!) 68K (likeways,
though I gather these chips do have a certain following) ARM (I've
heared an ARM-a-like is out in the open) SPARC, Mips Rxx000, or maybe a
nice classic Cray-like (i.e. Cray-1, clean cut single processor) 64 bit
design. The point there being that, other than clock rate & gate count,
(and we know that some limitations are good, from coding for BBC's,
right) the possibilities are more-or-less limitless.
On the down side, it would probably have to be a fairly-high end Vertex
to handle the job at all, and thus not at all cheap. But then its not
like a commodity PC, and those can also (for the foolhardy) run well
into four figures.
> Emulation will leave enough speed for a few factors of
> speed increase, compared to the real 2p. And it's more
> flexible.
Agreed.. There should be No problem for the ARM chip to emulate any of
the 8/16 bit processors at either standard, fast, or
absolutely-bloomin'-ludicrous-guv speeds.
Gahh.. All i need is 1 Masochistic VHDL guru, 1 workaholic C/Linux
Addict, and I can rule the world.. I mean of course WE can rule the
world.. I mean.. Oh sod it we'll just have to take turns...
BTW Did anyone get around to successfully ripping the ethernet core off
an old ISA network card and stuffing it one the 1MHz Bus? I'll have to
have a dig through my Generally Obsolete Network Cards Box. ISTR there
was a Western Digital 40 pin DIP Ethernet core that looked vaguely
interesting. No DMA, Interrupt and poll jobbie. How it ever worked on an
IBM PC/XT beats me. If identified, cards could be snapped up on ebay for
probably a quid each.
The other rather stupid ideas I had were, a replacement for the video
ULA.. Go on, tell me you love the stock one? Really?? No don't lie! THAT
is why the beem didn't do better in the market.. The graphics were erm..
Well I like modes 0,1,4 for graphics, and 3 for coding.
Woudn't it be nicer if all 16 colours were programmable? Grey scale
anyone? Now I know it /can/ be done externally, but its messy.. An
external video box (1Mhz bus) and replacing the cassette ULA with an
internal MIDI interface (I acutally got this to work.. ermm. 50% of the
time.. It was a clock phase thing IIRC. I was stealing a clock from
someplace (possibly the cassette ULA socket) and stuffing it to the
6850.. I still have the board someplace<tm> Now thats an easy beginners
project.
Cheers!
M.