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101090 discussions

by eric＠brouhaha.com

Does anyone know whether TurboDOS (an improved CP/M clone) is still available? A web search only turned up an entirely different TurboDOS for Atari computers. Cheers, Eric

27 years, 10 months

64bit data 128Bit address...Re: Building a Z-80 (64bit!!!)

by franke＠sbs.de

> As for a 64Bit data bus, there is no reason for a 64bit instruction but, > but with 64bits of data, you can do a hell-of-alot with video and signal > synthesis (i.e. sound). If you want to wrangle 64 Bit data you need to have acording operations - Wasn't it your intention to create a 64 Bit uP ? So, without a 64 Bit ALU and instructions to handle 64 Bit this Z80 will still be an 16 Bit uP just with an 64 Bit data bus. And for the Speed thing: it would be way better if the data bus is extended to 128 Bit, to reduce Memory access. With a 64 Bit bus in a 32 Bit CPU the theoretical bus load is just half. Or simpler: the CPU can be twice as fast with the same memory. > >And now tell me where you need 128 Bit address ? Just in > >case, even to fill a 64 Bit memory you need 4 GIG of > >mem thats just 4 grand ... and 128 Bit memory used ... > >oh unly 16,000,000,000,000 Dollar ... gee rich man > It is good design in my opinion to have your address bus twice as wide as > your data bus. Just tell me why ? Because it has been the tame with old 8 Bit uPs ? Come on thats just the stupid 'thats the way it always has been' idea. Address bus shuld be a) as wide as needed and b) if possible not exeeding the Size of the basic data unit. For a) just tell me where you need more than 4 Gig, or better where you need _way_ more than 4 Gig, because just 4 or 10 times this address space is easyer done with paging methods (wait for b)). And for b) you need special logic to perform address calculation, you can't hold one address in one regular register, you need more silicon to implement the adressing logic, adress calculation and (hidden) adressing register - you also need an additional ALU. > If you keep thinking like "you'll need $16,000,000,000.00 > in memory for that address size" you'll do the same stupid thing as: If you don't need it don't spent the silicon. > Micro$oft ("640K is more than enough for anyone"), Be carefull, now you're entering historical teretorry. MS-DOs was designed to use the full 1 Meg address space of the 8086/88. And could could well boot with something like 900 and more K user mem available. The 'Barrier' (640 or what ever) was given to DOS by the BIOS of the respective machine. And the PC-Bios had just to obey the CGA memory. > old programmers ("year 2000 is 20 years away. > This stuff will be obsolete by then"), You are just talking to one of them - and FYI we continue to use systems with two digit years and they are Y2K ready :) > and let us not forget Intel with their screwy memory addressing > schemes on their pre-X386s. Again, please think a bit - the x86 segmentation is a real great atempt to give - give more than 64 K Mem to a 16 Bit uP - allow an easy relocatable memory sceme - give a reliable memory base to a multi user/multi tasking OS I never had a problem with that - in fact I was realy happy about it (its just a kind of 16:16 base/offset addressing - remember /390 machines still have only one adressing base+offset - a proof for my belive, that base/offset is the only adressing mode needet anywhere). All the ranting about x86 are senseless and I often found (after taking out all the me-to-dont-like-it people) that these are the same guys who cant go well with 9 Bit machines or can't work with 7 Bit lines. > Think ahead! It wouldn't cost that much more or requrie much > more effort to add a few bits to the address bus. Just remember b) you NEED more effort, especialy things that don't fit into your standard modell. Just think, why was the Z80 so much better than the 8080 ? The 8080 implemented 16 Bit calculations, as needed for adress manipulation only as a kind of 'add-on', while the Z80 was more like a 16 Bit CPU. And here is also your additional effort visible - to give the flexibility to handle a address you need to implement 128 Bit things and operation - or you end up with a methods like the 64180 MMU or the x86 segmentation Or worse things like the page registers on the 65816 (I love the CPU, but I still think they should have used a x86 like sceme). And if your thinking about MMUs to expand a 64 Bit adress to 128, you just cut the adressrage down to 64 Bit, since external address enhancements are no design detail of a CPU. > Wow, I didn't intend for that to sound as sarcastic... No offence intended > Hans. Not taken - I still hope you will see it :) > As for the suggestion of using a DEC alpha to emulate a Z-80... I thought > about it but, those darned Alphas are way too expensive for us hobbist. Please ? An Alpha board with CPU is only a bit more expensive than a PC board with an equal Pentium. At least thats the street price over here in Munich - we have some PC part shops that are also selling Alpha boards and CPUs right aut of the blister. > Tell me more... what are Verilog, Xilinx or Altera? FPGA/GAL designs (and languages) some of them I think are already below the 3ns range. AFAIK you could aquire the Z80 design already as a FPGA description - add whatever you need and dump it into the FPGA. With 3nS you are able to get a 33 MHz Z80 right out of the box. Just don't forgett, a ready to use Z180 is 25% faster :) If you still want do try, you should realy dig into FPGA stuff (thanks Allison for the idea) here you get a nice sandbox to try your designs. And most of the evaluation kits are like for free. One more thing, when you want to design a 64 Bit CPU you will get something like 200 pins, so just forgett about any kind of DIL. > Anyone know if Zilog is going to beef up the Zx80 line???? Faster 180s and of course the 380s. But Zilog has to build things that will sell, so they are more into integrating special I/O devices than more CPU power. Gruss H. -- Ich denke, also bin ich, also gut HRK

27 years, 10 months

64bit data 128Bit address...Re: Building a Z-80 (64bit!!!)

by maxeskin＠hotmail.com

Please disreagrd this message! I'm really sleepy....I missed the fact that a 128-bit processor would access over 4 billion times the amount a 32 bit one would. I forgot all about the 64-bit ones. In this case, I would agree, and go as far as to say that humanity will _never access 300 tredecillion bytes, since to do so would require us to dissassemble several planets. This had been discussed when I wasn't paying attention... >contiguously (and would probably require a lot of hardware to access >it). There are plenty of tasks that can use up much more than 4GB ram, >most notably databases and various graphics. 1GB is currently the >amount of RAM a high-end server can be expected to have, and in CGI >and engineering applications, even this isn't enough. To sum up, >volume always fills capacity, as the highway engineers that are >tearing up boston haven't learned yet. But, what's the amount of RAM >a 128-bit processor can access? >>I beg to differ, and I'm willing to put my money where my mouth is. >I'm >>willing to bet $1000 that there will be no practical applications >requiring >>processors with 128-bit addressing by October 24, 2003. Any takers? >> >>> Yep. Short-sightedness (and history) is seemingly repeating on this >list. >> >>We'll see. >> >>This is not the same shortsightedness as the old series of claims: >> >> You'll never need more than 1K of RAM. >> You'll never need more than 4K of RAM. >> You'll never need more than 16K of RAM. >> You'll never need more than 32K of RAM. >> You'll never need more than 64K of RAM. >> You'll never need more than 128K of RAM. >> You'll never need more than 256K of RAM. >> You'll never need more than 512K of RAM. >> You'll never need more than 640K of RAM. >> You'll never need more than 1M of RAM. >> You'll never need more than 4M of RAM. >> You'll never need more than 16M of RAM. >> You'll never need more than 64M of RAM. >> You'll never need more than 256M of RAM. >> >>And yes, I've heard every single one of these statements made at one >>time or another. I haven't yet heard anyone claim that I'll never need >>more than 512M of RAM. My current Linux workstation has 384M of RAM, >>of which I routinely use more than 300M for large compiles (and I do >mean >>LARGE compiles, some require over 500M virtual) and for image >processing. >> >>Eric >> > >______________________________________________________ >Get Your Private, Free Email at http://www.hotmail.com > ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com

27 years, 10 months

More thoughts on building a Z-80 (64bit!!!)

by allisonp＠world.std.com

< It's a right pain to do complex digital circuitry like this. Great for < RF amplifiers, etc, but not so easy to run data buses across the board. < Although you _can_ make striplines using strips of copperclad stuck down < to the groundplane if you have to. for bussed logic is can work. The trick I used was 2sided clad board with one side sliced to produce 8 narrow strips as a bus with it's own groundplane. It was elevated over the chips with some screws (also passed the ground) and then wires picked off the needed signals. this approach was used to hook a 8049 MCU to a DDS (digital synth) that was used to drive a PLL. The core of a DDS is a (this case) 24bit parallel adder and 24 bit accumulator plus a 24bit constant register. A lot of parallel bussed signals. It was all clocked at 16.777216(2^24)mhz. A ram card would be harder but I've done one (dram!) that was fairly small (1Mx8 using 256kx1 dips) and one off. busing is a pain only in that it's a lot of repetitive wiring. But being visible it was easy to see signal progression. The results worked well and lacked the ringing that sometimes plagues boards of two sided design. Allison

27 years, 10 months

Why do some of us collect old computers ?

by allisonp＠world.std.com

< Why do some of us want to collect these old computers. ?? As an engineer I like to study old computers as there were often some good ideas or neat tricks encapsulated in them. To have machines off the track I followed (intel/z80 or DEC). This leads me to to aquire Kim-1s, Trackstar128s and the like. To have and use machines I didn't own but worked with. Like PDP-8s, Vaxen SDK85s, sdk88s and others. To extend, modify or otherwise use the systems I did aquire over they years. I may be unique as many of the oldest machines I have are orginal purchases. I have and use machines I could not afford in their time. Systems like the Compupro, Visual 1050, PS2/50z are examples of this. All of my systems are operational, many are used daily or weekly. Allison

27 years, 10 months

Starting from Scratch (was Re: OT: Modern college educa

by franke＠sbs.de

>> Ah! I misunderstood. That's a cool idea. There is an open source >> version of Civilization floating around. Perhaps that could be >> adapted, not that we couldn't steal a start from somewhere else... >> My Lord Hammurabi, I beg to report to you that this year we >> have produced 1,000 transistors and 400 rallods of copper >> wire. >> How much copper do you want smelt this year? Wow - thats it - I 've been already eaten up by megagraphics. So, anything I could Imagine was to reduce graphics to ASCII ... but Yo thats it Hamurabi ! > I don't know about that -- it would make the game rather difficult. > Rats have eaten 320 transistors. > Do you want to buy or sell stock? > Or maybe that should be: > Surplus shops have taken 215 transistors. > Do you want to buy or sell source code? Pfffft. Go ahead. thats great! Where is my copy of '101 basic games' ? Gruss H. -- Ich denke, also bin ich, also gut HRK

27 years, 10 months

Week End Finds

by fauradon＠pclink.com

Hi Mike, Did you receive your PC-1500 yet? Francois ------------------------------------------------------------- Visit the desperately in need of update Sanctuary at: http://www.pclink.com/fauradon/ -----Original Message----- From: Mike <dogas(a)leading.net> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Monday, October 19, 1998 8:20 PM Subject: Re: Week End Finds >>Does any one have docs on the pc-1500? Any info would be appreciated. A web >>search didn't bring anything more than the specs, I would like to find >>programming info if that is possible. >>Thanks >>Francois > > >Hi Francois, > >I just ordered one of these machines ( inbound mail ) send me some mail to >dogas(a)leading.net I should have it by week end... >- Mike >

27 years, 10 months

Educational subsidies

by maxeskin＠hotmail.com

Slashdot.org has a story explaining that the UK school system can't afford NT 5 and are considering another OS. In light of this, people were bringing up Apple's success in schools in contrast to the current situation. However, I have heard that the only reason why Apples were common in schools was that the gov't bore some of the price tag to encourage use of Apples, and Apple didn't pay as much attention to education as is generally thought. Is this true? What were the particulars of Apple educational licensing? ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com

27 years, 10 months

Odd Meas. Units

by mbg＠world.std.com

>> I used to know the speed of light in Furlongs per Fortnight. > >The attoparsec/microfortnight is remarkably close to the inch/second. >Quite useful for quoting tape speeds :-) IIRC, the GT40 lunar lander program had comments about measuring things in furlongs per fortnight. I'll have to check the source... Megan Gentry Former RT-11 Developer +--------------------------------+-------------------------------------+ | Megan Gentry, EMT/B, PP-ASEL | Internet (work): gentry!zk3.dec.com | | Unix Support Engineering Group | (home): mbg!world.std.com | | Compaq Computer Corporation | addresses need '@' in place of '!' | | 110 Spitbrook Rd. ZK03-2/T43 | URL: http://world.std.com/~mbg/ | | Nashua, NH 03062 | "pdp-11 programmer - some assembler | | (603) 884 1055 | required." - mbg | +--------------------------------+-------------------------------------+

27 years, 10 months

Fairchild Channel F

by fauradon＠pclink.com

Hi, I finally got around to going to the thrift store and picked up that Channel F. It cost me $10 and has Carts number 12 Baseball and 16 Dodge it. Whoever wanted it please respond to fauradon(a)pclink.com Francois ------------------------------------------------------------- Visit the desperately in need of update Sanctuary at: http://www.pclink.com/fauradon/

27 years, 10 months

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