John Floren wrote:
> Well, I wasn't thinking the MC68000 processor exactly, just something
> from that family. I *do* have some experience with FPGA, so I'll
> consider doing that as well.
So check google/wiki for Minimig. It is an amiga 500 clone with a real
mc68000 cpu and all peripherals in an FPGA.
Seems to be a lot of fun.
Cheers
Mark Haysman wrote:
> Hi.
>
> The X2 class capacitors fail, causing that smoke.
That seems the most likely cause to me. I don't think I've ever seen a
transformer in a switchmode supply go into meltdown. Not that shorted windings
can't happen, but it's a very uncommon failure IME...
cheers
Jules
Actually, Nolan and Ted Dabney's first foray in to video games. The two designed and built it together.
Always amazes me how Nolan's PR over the years has effectively wiped Ted's contributions, and in some cases sought to rewrite history.
Marty
----- Original Message -----
From: "Adrian Graham" <witchy at binarydinosaurs.co.uk>
To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
Sent: Saturday, December 13, 2008 11:26:13 AM GMT -06:00 Central America
Subject: Re: The first video game
On 13/12/2008 15:14, "Liam Proven" <lproven at gmail.com> wrote:
> I never knew there was a coin-op Spacewar!
>
> http://www.theregister.co.uk/2008/12/13/tob_computer_space/print.html
Yep, it was Nolan Bushnell's first foray into video games but didn't get too
much money because it was too complicated for the 'average' user. From my
own Atari page:
" Whilst working at Ampex (creators of the first practical video recorder no
less), Nolan Bushnell had already created an arcade video game based on
Spacewar, which was a game written by Steve Russell in 1961 for the PDP-1
>from Digital Equipment. Nolan's version was called Computer Space and it was
being distributed by Nutting Associates. However, it wasn't as popular as
he'd have liked (he said you had to read the instructions, and people didn't
have the patience!)"
--
Adrian/Witchy
Binary Dinosaurs creator/curator
Www.binarydinosaurs.co.uk - the UK's biggest private home computer
collection?
Wirth was at Stanford at the time and there is a Stanford Tech Report
that gives the grammar and usage of Algol W.
I presume everyone knows the joke; Wirth is call by name in Europe and
Call by Value in the US.
IMHO (but of course), the significant contribution of 'W is Call by
Reference and Call by Result.
>
>Subject: Re: Bootstrappable language
> From: "bfranchuk at jetnet.ab.ca" <bfranchuk at jetnet.ab.ca>
> Date: Thu, 11 Dec 2008 12:27:12 -0700
> To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org>
>
>Dave Dunfield wrote:
>> You don't need register to register operations to support a C compiler.
>>
>> Can you provide any details of your architecture and instruction set?
>>
>> It might be feasable to make a port of my Micro-C toolset to it... If
>> not, it might be feasable to make a port of "C-flea" a virtual machine
>> I designed specifically to support Micro-C (I've supported some pretty
>> weird architectures by employing C-flea).
>>
>The architecture is like I said before a stretched PDP-8, with a
>512 byte direct addressing range and more compleate set of alu operations.
>I am exploring the idea that 18 bits is still the best size word size
>for a small
Have you lookd at DG Nova? Sounds like your traversing that same path.
>computer or digital controller. The extra opcode bit is used to
>support word &
>byte sized operands, compared to the that of a 8 bit micro. The two more
>address
>bits negate the loss of byte addressing and give a bit more room for a
>resident
>OS rather than swapping core in and out.
>
>Using CPLD's also gives me the feel that a 18 bit simple cpu like my design
>could have been developed as microchip computer similar to 6800 or 6502
>chip set around the time the Z80 was developed. Using 48 rather 40 pins
>as packaging a 18 bit cpu with front panel support could have been
>developed.
>
>A) Cpu chip. B) Swr/data/address bus display support chips . C)
>data/byte swap buffer.
>
>> Micro-C is a very small, but reasonably powerful dialect of C - For an
>> example, refer to the ImageDisk sources on my site ... ImageDisk and all
>> of it's utilities are compiled with the PC version of Micro-C (as are my
>> simulators, transfer tools and pretty much all of the other DOS based
>> tools I've posted).
>>
>> Dave
>>
>> Btw: If you haven't written an assembler yet, let me know - I've got a
>> universal table driven assembler generator which I developed to rapidly
>> produce assemblers for many of the later architectures I supported.
>>
>>
>Unlikely it will work , I have 9 bit bytes.
>I have hacked, Jones's PDP 8 assembler to cross assemble for me.
>Once I get the the single PCB board built later next year, then I
>will consider porting Micro-C. I plan to only have about 64Kb +
>bootstrap EEPROM, IDE interface and a two 6850 uarts
>along with a front panel. I am not sure yet if the IDE interface will be
>16 or 9 bits wide yet.
>
A table driven assembler can produce anything.
Also a stack based language or even C can have the anythig stack related as
multiple instructions only code efficientcy suffers and code size.
An alternate way to go is a small emulation engine written in assebler to emulate
a easier to compiler for virtual machine (P-code).
The IDE can be 9 bits as the upper 8 (or less) bits are only used for data and a
non required ops. I've done that for 8bits to simplify the interface and the
only cost is 50% of the data space was not used, a minor nit as I had 500%
more than needed.
Allison
I see one response saying that they predated the electronic stored program computer by about 40 years. Perhaps, I wasn't around that early.
But I recall a GE installation at a university of the late 1950's that had the raised floor that became standard in the 1960's. As were a couple of IBM 7xxx systems.
OTOH, a 650 I knew in 1957 was on concrete, as was a 1401 as late as 1967.
Cabling was an issue, cooling the other. The 1401 was in a well-air conditioned room, and the cabling was OVERHEAD!! Damn cheaper than raised floor. Until the large systems of the middle 1960's required cabling be out of the way, it was as much a matter of convenience as anything else - you need to be able to truck trays of cards, paper, tapes in and out, and cables made that a problem.
I'd be interested in the turn of the 20th-century-raised floors. Must make a note to look that up.
Vern
--- On Tue, 12/9/08, William Donzelli <wdonzelli at gmail.com> wrote:
> From: William Donzelli <wdonzelli at gmail.com>
> Subject: Raised floors
> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
> Date: Tuesday, December 9, 2008, 6:08 PM
> Here is an aspect of computer history not yet touched - when
> did the
> industry standardize on the 2 x 2 raised floor? Certainly
> they were
> common in the 1960s, but were they standard in the 1950s?
>
> --
> Will
>>>>>
> So, has anyone come across a good online resource which compares
> vintage CPU
> instruction sets? It'd be useful to see what 'core' instructions*
> were most
> common back in the day and use that as a basis for my own homebrew
> effort;...
Have a look here:
http://www.ourcomputerheritage.org/
Around 40 machines from 1950 to 66.
17 machines from Elliott, 11 Ferranti, 3 Leo, 4 English Electric, 2
BTM and 5 ICT.
For me the Elliott 900/920 series is particularly interesting, 4 op-
code bits, a B line modifier and 13 address bits. I worked on
compilers for this before writing one for the Zilog Z8001 to replace
the 920 ATC. The language was Coral 66, and Algol 60 derivative for
real time computing.
The 900 had no OR,XOR or NOT instructions, but it did have a negate
and add instruction, and if you had a word in memory holding the
constant -1, then a negate and add -1 could be used to do a NOT. From
this and the built in AND instruction could be built the other bitwise
logic operations.
There is no subtract operation either which meant that the order of
evaluation had to be changed around within the compiler to use the
negate and add instead.
The other conditional jumps had to be constructed from jump zero, jump
negative and unconditional jump.
Increment but no decrement.
No stack, no immediate operands, an accumulator (A) and a right side
extension (Q) and a B register which could be used to modify any
instruction allowing access to all 256k memory words (though only 128k
of program).
No carry flag so multi word arithmetic was hard work, including
software floating point, thankfully built into hardware in the 920ATC.
My other personal interest is the ICT 1301 which is memorable for
having no program counter, in being 4 bit parallel, 12 digits serial,
having no indexing instructions and being programmable purely in
decimal. Even core memory is decimal, if you try to execute a non
decimal digit the machine would stop at instruction fetch. If you
directly hand key an instruction with a non decimal digit in the
address field, the core memory will not respond (the CPU sees a zero)
and stop the machine with a parity error unless parity checking has
been turned off.