Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 


Forgot your password?
Close
typodupeerror
×
Hardware

Zilog To File For Chapter 11 255

Posted by Hemos from the death-of-the-old-timers dept.
Frédéric writes: "The venerable company ZiLOG who was founded in 1974, and who brought us the famous Z80 CPU (used in the Timex/Sinclair ZX80/ZX81, and the Amstrad CPC/PCW computers), is filling for Chapter 11 ... I didn't find the today's news on the web, but found this article at Silicon Strategy and this one at Electronics times, which was written a few days ago to announce it."
This discussion has been archived. No new comments can be posted.

Zilog To File For Chapter 11 More

Zilog To File For Chapter 11

Comments Filter:

  • Dont forget our favorite ones. (Score:3, Interesting)

    by GiMP ( 10923 ) on Friday December 07, 2001 @12:40PM (#2671469)
    Z80 also powered the sound chip in the Sega Genesis and a modified chip was used in the Gameboy.

    • Re:Dont forget our favorite ones. (Score:4, Interesting)

      by LordNimon ( 85072 ) on Friday December 07, 2001 @12:42PM (#2671482)
      And the CPU in many of the TRS-80 computers.
      • wasn't the 8088 a ripoff of the z80?

        Thats what I heard years ago....
        (Never seen the z80 instruction set.)
        • I always thought it was vice-versa. Except that Zilog improved on the 8080 design, quite a bit.

          • Re:Dont forget our favorite ones. (Score:4, Informative)

            by coolgeek ( 140561 ) on Friday December 07, 2001 @01:23PM (#2671738) Homepage
            Yep, the 8080 came first. The Z-80 second.

            The Z-80 added block i/o and block move instructions, along with a mirror register set. Mostly, one would avoid these instructions to provide compatibility for the 8080-using luddites of the time. Sure, it was possible to detect. We would opt for smaller code size many times as 64K was the limit unless of course the machine was of the nifty bank-switching variety. Every byte used by the BIOS took away from CP/M's TPA (Transient Program Area, the limit on the size of the application). BITD, some vendors beat out the competition on TPA size alone.

            The mirror register set was a real bonus over the 8080. It took only a handful of clock cycles, and was way cheaper than pushing/popping in an ISR.

        • Re:Dont forget our favorite ones. (Score:4, Informative)

          by blamanj ( 253811 ) on Friday December 07, 2001 @12:52PM (#2671554)
          No. The 8088 was a "bus limited" version of the 8086, Intel's first generation of the x86 architecture.

          Internally, the 8088 was identical to the 8086, same registers, same instruction set, but it had the advantage of working on all the 8-bit bus infrastructure.
          • > Internally, the 8088 was identical to the 8086,


            almost. There was a very slight difference that you could detect with self modifying code. If memory serves, it fetched/catched the same number of 8bits as the 8086 did 16bits. You could write a jump that would get cached in one and not the other, or somesuch, to figure out which one you were using.


            hawk

        • wasn't the 8088 a ripoff of the z80?

          No. If I am not mistaken, the story goes like this:

          8080--->8088/8086 -> *x86 (Intel)
          \-->Z80 (Zilog)

          With various extended and enhanced such as the Z80A from Zilog (faster version) or the 8088-2 from Intel (the one I had in my first PC).

      • Commodore too (Score:4, Informative)

        by mmontour ( 2208 ) <mail@mmontour.net> on Friday December 07, 2001 @01:02PM (#2671618)
        Yes, even Commodore used a Z80. Specifically in the C-128, which could boot into a CP/M mode running on the Z80, or into regular C-128 mode on the 8502, or into C-64 emulation mode (also on the 8502). I don't think there was any way to run both CPUs at the same time.

        I don't know how many people actually used this feature (probably not many, given how well the C-128 did in the marketplace), but it was kind of neat at the time.
        • I don't think I ever booted into anything BUT c64 mode after the first day I had my 128. Mmmm... F16 Combat Pilot... and let's not forget Montezuma's Revenge!

        • I don't know how many people actually used [Z80/CPM on the C128] (probably not many, given how well the C-128 did in the marketplace), but it was kind of neat at the time.
          I had a C128 back in the day, and checked it out (partly out of curiosity; partly in search of an OS more cabable than Commodore Basic). The problem was
          1. Unlike Commodore BASIC (where everything is burned into ROM), CPM is a disk-based OS
          2. The C1541 (the standard floppy drive for the C64/C128) was miserably slow, even after various speed-up tricks were employed.
          There was also the chicken-vs-egg problem here: nobody primarily interested in running CPM was going to get a C128, and few (if any) C128 owners that didn't know CPM were going to bother to learn without good reason.

    • Re:Dont forget our favorite ones. (Score:1, Informative)

      by Anonymous Coward
      Don't forget most of the TI graphing calculators. . .
    • The Zilog Z-80 is was used in many embedded applications...I think it's being used less and less now, but I can think of a few devices off the top of my head that are still Z80 based. The Sharp Wizard electronic organizer is one example, the Gameboy is another. It's probably used in a lot of things you wouldn't think of, like phones and such too.

      • You do find Z80 cores inside several mobile phones that are still sold today. Most vendors are now switching to ARM or other (more recent) processors, but there are still many Z80-based phones out on the market.

        The core of the processor is usually integrated in a chip that contains other systems as well, but this is still the good old Z80.

        I still have my Sinclair ZX Spectrum (sold as Timex in the US). Ah, the good old times... I remember programming this thing in assembler (most of it assembled by hand, of course - the Zeus assembler was too slow to load) and counting the clock cycles to make some nice animations on the TV screen.

      • The Z180 (and a variant from Hitachi, the 64180 (?)) sees a fair amount of embedded use as well. The SCSI card in my Apple IIGS, a RamFAST, uses either a Z180 or 64180 (depending on the revision) as a cache controller and DMA controller. It also implements the on-board tape-backup software...you could go into the card's firmware and tell it to back up one or more partitions to tape. You could then exit back to ProDOS (or whatever) and keep doing stuff while the backup was running (the affected partitions were locked to read-only while the backup ran). A clever trick, especially for what's now an 18-year-old computer.
      • Manufacturing makes big use of the Z80 processor in PLC's. In the several years I was the senior electronic technician at a wire making plant, I have never seen a Z80 make a mistake. If industrial cable sells for $80 a foot at 30 feet per minute, a Z80 really shows its value.

        A $1 Z80 processor is priceless. Their sucessors may have more fancy bells and whistles, but the Z80 may live forever. The Z80 may never die. And I hope not. It was the first processor I learned assembly and the most fun to work with.
      • I write Windows software for managing a brand of access control panels that still use Z80's. I don't deal with the firmware or anything, but the company has obviously decided to stick with something that works!

    • UK Perspective (Score:3, Informative)

      by lordpixel ( 22352 )
      In the UK, Sinclair computers and their derivtives were huge - much more well known than the US Timex TRS-XX machines (though geeks here seem to remember them fondly:

      IIRC, all these machines had some Z-80 derivative:
      ZX80 1K RAM (actually named after the year it came out)
      ZX81 1K or 16K RAM
      Spectrum (development codename ZX82) 16K or 48K RAM [+]
      Spectrum + (larger, "better" keyboard)
      Spectrum 128 (a vast 128K of RAM)
      Spectrum 128 +2 (built in cassette deck!)
      Spectrum 128 +3 (build in 3" *not 3.25"* 2 sided (by ejecting it and turning it over) floppy disk)

      There were a couple of others.
      Then also things like the
      MGT Sam Coupe - which was compatible

      I, my family or my firends owned every single one of these fine Z80 powered machines at one time or another. Hell, I learned to program in Sinclair basic. If Zilog have gone under (Chapter 11 doesn't mean its necessarily over) this is a sad day.

      [+] actually this was a marketing lie. It had 32K RAM and 16K ROM with a unified address space. I think the 16K version had the same ROM, so it would be fairer to call that a 32K, if you want to include the total...

      • Re:UK Perspective (Score:3, Informative)

        by komet ( 36303 )
        [+] actually this was a marketing lie. It had 32K RAM and 16K ROM with a unified address space. I think the 16K version had the same ROM, so it would be fairer to call that a 32K, if you want to include the total...

        Not true. The Spectrum 48K hat 48K RAM consisting of the standard 16K augmented by a separate 32K bank. There was also a RAM pack with 32K in it which you could plug in to the 16K Spectrum.

        Along with the 16K ROM (which was identical in both versions) the 48K Spectrum filled up the entire 64K Z80 address space.

        Yes, I do know the Spectrum architecture like the back of my hand... :)

      • Re:UK Perspective (Score:4, Informative)

        by Howie ( 4244 ) <howie@@@thingy...com> on Friday December 07, 2001 @04:48PM (#2672965) Homepage Journal
        [+] actually this was a marketing lie. It had 32K RAM and 16K ROM with a unified address space. I think the 16K version had the same ROM, so it would be fairer to call that a 32K, if you want to include the total...

        Nope - it was 16K + 48K in a 64k address space. What you might be thinking of is the following though: at least one issue of the spectrum PCB was designed to use 'broken' hitachi 32k chips, in which the top half was dead, since sinclair had gotten a batch of them cheap. Considering his first business in the 60s as a teenager was buying 'dead' transistors from Mullard and re-testing and re-labeling them to their true spec for sale to impoverished hobbyists, this story holds water to some degree.
    • Z80 also powered the sound chip in the Sega Genesis and a modified chip was used in the Gameboy.

      Yes, not to mention the TI-81, 85, 86, 82, and 83. Fine machines, they were...
    • ...the Sharp Wizard OZ-770PC. [sharp-usa.com] It's amazing! 3MB of flash ram, qwerty keyboard, proportional fonts, you can code in raw Z80 assembler for it, plus they have versions of C and BASIC for it. Tons of user written programs on the net. (MyWizard.com [mywizard.com] and many other sites) Best $100 I ever spent. I much prefer this design to a Palm-style tablet. Here is a good picture. [amazon.com]

      And no, I am not affiliated with Sharp or Amazon ;)
    • Genesis was a 68000... same chip as amiga 500/2000

      http://www.zophar.net/tech/genesis.html
    • The Z-80 was also used in some mid-80s electronic musical instruments, like the LinnDrum and the Oberheim DMX drum machines.

      IIRC, the Oberheim DX and Ensoniq Mirage had 6502s and Emu prefered M68000s.

      k.
  • It was also used to run many classic arcade machines such as Pac-Man.

  • And TRS-80's, too! (Score:2, Informative)

    by mr.nicholas ( 219881 )
    Don't forget that the Z80A was the CPU for TRS-80 model 1's & 3's, too. It was the first assembly I learned and it taught me a vast respect for memory conservation (4K was all that was available at the time).

  • best z80 instruction (Score:1, Funny)

    by Anonymous Coward
    was MBSSR (make baloney sandwich and shift right one bit)
  • Can you do anything with an 8-bit microcontroller anymore? :)
    Although putting an embedded web server on a Z80-based machine is kinda cool.
    • Go read Von Neumann and Turing.

      You can do ANYTHING with an 8-bit microcontroller. It just isn't necessarily easy.
    • ``Can you do anything with an 8-bit microcontroller anymore? :)''

      The smiley indicates that you were probably joking. But... there's probably enough brainwashed budding engineers out there who will take it for granted that they need a Pentium class microprocessor to power the next programmable Mr. Coffee. They probably want to use Windows CE, too. Just you wait. Laziness will result in your ``smart'' kitchen appliances requiring muffin fans to keep the processors cooled.

      (Damn but I'm cynical today...)

  • TRS-80 (Score:2, Interesting)

    by LumpyCartman ( 539950 )
    Also the Early Radio Shack Machines. TRS-80 Model 1 through 4. I once had a Model 6000 running XENIX that had both a Motorola 68000 and then a Z80 for I/O functions

  • Damn (Score:2, Interesting)

    by HuangBaoLin ( 13109 )
    As a owner of a fully decked out TRS-80 Model I, II and Timex Sinclar 1000, I'm sorry to see them go under. I bet a lot industrial and robot controller companys aren't to thrilled ethier as the CPU has been a sort of staple for them for quite sometime.

    I guess the PIC / microcontroller chip market really took over, leaving little room for Zilog...
  • Aren't the newest TI calculators based around a Z-80 alike chips?

    What about second sources?

    • Only the ti-86 and lower have z80 chips. The ti-89, ti-92, and the ti-92 plus all have motorola 68k processors. If you've seen em in action, they graph a lot faster than the z80. Of course, the z80 calculators are just fine for most graphing.
      • The TI-82,83,85, and 86 are the ones MOST people use. These calculators are still sold and in great numbers I might add. They all use Z80 processors and, for the most part, run great.

        I used to laugh that I had two Z80s in my room (one in my Sega Genesis(with a 68k in my Sega CD), and one in my calculator) which were performing completely different types of operations. At least until I got my hands on Zshell and the like for my TI-85 and started playing tetris on it all the time.
        • you should definately use USGuard rather than zshell. Much faster and less space, i believe. The later version of tetris that i had only ran in usguard, but it was 2 player (link cable) and ran fast as crap.
          Zshell stood for Z-80 shell, by the way.

          You can find out information about usguard here [ganymed.org], which seems to be broken. The download is also available at this page which is [ticalc.org]. There's also mucho information here [ticalc.org].

          ~z

  • Doesnt sound too bad (Score:5, Informative)

    by michaelsimms ( 141209 ) on Friday December 07, 2001 @12:46PM (#2671516) Homepage
    From a press release pre-chapter 11, they state:

    ZiLOG intends to launch an exchange offer in which all holders of its notes will be offered the opportunity to exchange their notes for shares of ZiLOG common stock, plus a pro rata share of the $30 million non-recourse note. The exchange offer, which for tax and other legal reasons the company intends to complete through a prepackaged Chapter 11 filing, is not expected to have any adverse affect on its day-to-day operations or on its ability to provide a full range of products and services to its customers or pay its suppliers on normal terms.

    I dont think we have much to worry about here.

  • The Z80 is also used in the venerable TI-85 [ticalc.org] calculator, and related models.
  • I'd be sad to see a company that's such a piece of microprocessor history disappear.

    My first computer was a 1978 NASCOM-1 kit (a board, bag of chips and seperate bare transformer!) that was based on a 1 MHz Z80 with a whopping 2K of memory - 1K for the monitor program, and 1K for the user. Back in those days we programmed from memory directly in hex - none of this fancy modern symbolic assembler stuff!

    Zilog also had 16 and 32 bit microprocessors, but neither took off - the Z80 has had a long life though.

    The story of the Z80 is quite interesting - the design of the Intel 8080 basically walked down the road in the head of the designers who then designed the Z80 which was close to being dual 8080's on a single die - with it's dual A and A' register sets.

    Ah, the good old days.... :-(

  • Bankruptcy (Score:4, Informative)

    by displaytest ( 31803 ) on Friday December 07, 2001 @12:54PM (#2671573)
    Remember, this is not an involuntary bankruptcy (at least not completely). Zilog is filing a "pre-pack" which means that they've gotten together in advance with all of their creditors and gotten them to exchange their debt for equity. Zilog will not disappear - in fact, this really only stands to make them financially healthier.
  • Interestingly, the just shipped [zilog.com] a new eZ80 webserver three days ago.
  • Intertec's Superbrain [old-computers.com], built around 1979, had dual Z80s (one for diskette I/O and booting, the other for everything else). 16k of DRAM - expandable to 64k with a soldering iron. It ran CP/M 2.2. I last used it in 1989 for a college project.

    • That reminds me. I think the MFM controller in my old ALR 386/2 used a Z80 chip. Those chips did get around but then an entire generation of engineers learned the 8080 or Z80 instruction set in college (another big one would have been the 6800/6502). It's not surprising to find the chips in lots of equipment designed in those days.

  • Go ahead, tell me I am trolling, but how on earth did a company with an ancient, 8-bit architecture manage to get idiots to throw $280M at it? My cat will design you an old 8-bit architecture for 1/10,000 of that and I promise she won't file for chapter 11.

    Did they REALLY expect a Z80 with a TCP/IP stack to set the world on fire enough to pay back $280M? QUARTER OF A BILLION DOLLARS!?!?!

    • Re:$280M debt? (Score:4, Insightful)

      by Pig Hogger ( 10379 ) <pig DOT hogger AT gmail DOT com> on Friday December 07, 2001 @01:01PM (#2671610) Journal
      Did they REALLY expect a Z80 with a TCP/IP stack to set the world on fire enough to pay back $280M? QUARTER OF A BILLION DOLLARS!?!?!
      You seem to forget the embedded/controller market. There are zillions of devices in the field based on Z-80 controllers, and gillions of software written for it. This is something you just don't throw out overnight.

      And a instantly-networkable Z-80 will definitely fill some needs, if only for the plentifulness of implementing distributed systems via TCP/IP.

    • Both MicroChip and ubicom (Former Scenix) are very successful in the 8-bit microcontroller with tcp/ip support.

      A small controller with TCPIP can be used in many places. Cars, electrical kicthen stuff etc.

      There is work underway that will place a microcontroller in each wall-plug so that you can control light and power for your entire household. Thoose designs needs a lot of microcontrollers with network support.
    • You validly point to the location of the problem, if not necessarily the putative cause of the problem.

      Yes, indeed, if they've spent $280M of borrowed money, and have nothing to show for it, that's a problem.

      Zilog has a history of trying some ambitious things: some may remember the Z-8000, and even the Z80000, which attempted architectures of rather higher-bittedness. None "succeeded."

      If their latest attempt at "huge growth" failed, that would nicely explain there being a big debt hanging around as a millstone to sink the stable bits of the business.

    • Comment removed (Score:5, Informative)

      by account_deleted ( 4530225 ) on Friday December 07, 2001 @01:21PM (#2671728)
      Comment removed based on user account deletion
      • Although your rant has merit, you picked on the wrong rantee. I work for a fabless semiconductor company architecting extremely low-cost 8051-based smartcards. And it is 8051s that own the mass 8-bit market; Z80 & HD64180 are passe. This has been the case for years, hence my original point about complete dunderheads being required to cough up that amount of money on a game plan based on a dead architecture.
    • ...but there are other things she won't be able to do that will hinder the success of her chip in the embedded market. My cat could probably also design an 8-bit processor, but the documentation process - in fact, the entire support process - needed to bring a chip to market would be a little beyond her. Without opposable digits, she would be unable to type up the whitepapers and specs, and without the power of speech, she would not be able to dictate this information. So, unless my own cat blatantly copied an older processor, no one except her would be able to develop for it.

      Of course, if my cat did manage to successfully document her chip, I'm sure she's sell it for a reaonable price - a lifetime supply of canned food, say. She and I both know that's a little steep for an 8-bit chip, but who can say no to my adorable little cat?
  • when i first reloaded the page, i saw the Z in Zilog and thought, 'Jesus! Zapmedia went out of business already? Now that's some /. effect.'
  • There is actually a Z80 in the new Gameboy Advance. This is for providing the Gameboy Color compability mode.
  • Once people started writing emulators for all of the old classic computer systems, there was no reason for anyone to go out and buy the real thing. The hackers stole the liveleyhoods of the Z80 designers. I hope they can sleep at night.
    • Look, nobody's gonna buy an 8-bit personal computer these days. The only use for Zilogs is in embedded apps, and that can't be emulated away.
  • Better stock up on this collector's item:

    Z80 assembly language subroutines
    by Lance A. Leventhal

    Availability: Seller usually ships in 1-2 business days

    ASIN: 0931988918
  • Sigh. Tears well up in my eyes. My first paying job out of school was writing Z80 assembly code for the Sega GameGear and Nintendo GameBoy (a crippled, cheapo Z80 on the Nintendo).

    And I suspect there were a bunch of arcade games that ran a Z80 besides PacMan.

    Rest in peace, my little 8 bit friend, RIP.
  • "Once we successfully address the issue of our senior notes, ZiLOG will be well positioned to compete during this difficult period and to take full advantage of the eventual economic recovery," Thorburn said.

    They filed chapter 11 for strategic reasons, not because they'd gone totally bust.

  • Think you know your Z80 code? (Score:5, Interesting)

    by dstone ( 191334 ) on Friday December 07, 2001 @01:15PM (#2671699) Homepage
    Pop quiz, hot shot. Tell me what this Z80 code does...

    LD BC,0FFFFH
    LOOP: DEC BC
    JP NZ,LOOP
    • I suppose the specifics depend on your processor speed, but that's a delay loop.

      If I recall correctly, a 16-bit load took 4 t states... Damn. it's been far too long.
    • I can't believe no one got this right yet.

      It looks like a delay loop, but the 16-bit increment and decrement instructions don't modify the zero-flag, so it either executes once or loops forever.

      You probably want:

      LD BC,0ffffh
      LOOP: DEC BC
      LD A,B
      OR C
      JP NZ,LOOP

    • Trick question. It's an infinite loop.

  • ORG 1800H (Score:2, Interesting)

    by er0ck ( 267290 )
    I rememebr programming a Z80 Microtrainer in college; it had a keypad for hex code, but I managed to smuggle in a friend's copy of the ZAD cross-compiler to the lab. We had these old 286's with serial-to-headphone jacks that connected to the microtrainer. You typed in your assembly code on the 286, ran it through ZAD, and uploaded it to the microtrainer. You could even hear the data being transfered via the speaker on the microtrainer.

    I remember having my first real experience with handling Interrupt Requests in a lab with the Z80. Too bad the company is having trouble.

    I tried to find a pic of the old microtrainer (made by CAMI Research [camiresearch.com]), but alas, they no longer support it.

    I did manage to find a link to another University that used them for ECE projects. (Thanks Google! [google.com])

    http://comet.ctr.columbia.edu/msl/2000class/elevat or/ [columbia.edu]

  • Zilog literature police contributed to problems (Score:3, Interesting)

    by Anonymous Coward on Friday December 07, 2001 @01:22PM (#2671734)
    In the last several years it became harder and harder to get literature from Zilog. When new management took over a couple of years ago, most of the legacy PDFs disappeared from the website. Trying to order literature directly was a nightmare.

    Zilog not only made processors but also a rich array of peripheral chips including SCSI chips used in earlier Sun and Macintosh workstations. Unfortunately, Zilog got too big for its britches and forgot who brung them to the dance: small independent software developers. In recent years, unless they thought you were going to place an order for one million chips, their attitude became "go away, son, you bother me."

    Can't say that I'll cry any tears for Zilog.

  • Do you people know anything? (Score:5, Informative)

    by Anonymous Coward on Friday December 07, 2001 @01:22PM (#2671735)
    Chapter 11 - Chapter 11 of the Bankruptcy Code is frequently referred to as "reorganization." Although an individual may file under Chapter 11, generally it is used to reorganize a business. Individuals with large federal or state tax obligations may use Chapter 11 because an extended period of time may be obtained for the repayment of the taxes. Chapter 11 generally allows the debtor to continue its business operations as it proceeds to the desired goal of a confirmed Plan of Reorganization, which must meet certain statutory criteria. A major rationale for business reorganizations is that the value of a business as an ongoing concern is greater than it would be if its assets were liquidated and sold. Generally, it is more economically efficient in the long run to reorganize than to liquidate, because doing so preserves jobs and assets. Cooperation among the various interests, however, is crucial to a successful reorganization.

    Chapter 7 is liquidation where basically everything is gone. Chapter 11 doesn't necessarily mean death for a company. Hell, look at Chrysler.

  • The joys of Z80 ASM (Score:2, Interesting)

    by Anonymous Coward
    Well, I am not as old as some of you guys, but I remember the very day I got my TI-85. The first thing I learned (in about a week) was TI's Basic language. I quickly became bored with that because it did not offer the programmer a whole lot of options. I then discovered that the TI-85 could be programed in ASM... at that point I did not know ASM at all (well besides an inline ASM line I used in Turbo Pascal to turn off the damned blinking cursor) so I bough a book on Z80 ASM.

    After a couple of months I came out with my first ASM game, yea it wasn't all that great but it paved the road for the following games. In those next three years I released 8-9 pretty darn good games for the 85, after that I got a shiney new TI-86 and never touched the 85 again (but again it had a Z80, and a TON more ram to work with). I programed a few games for the 86, but I had slowed down a lot from when I had first started.... I guess I began to get a little bored.

    I had a lot of fun with the Z80 cpu, its ASM language was pretty easy to get the hang of, and it wasn't a slouch.... my games ran fast. I no longer am a part of the TI community, I have moved onto bigger and better things (let me tell ya, knowing ASM in college was awesome.... my asm classes and computer architecture were much easier :) )

    I know there optimizing compilers exist... and they are darn good at what they do, but still there is nothing like optimizing key functions in your code by hand.... Thanks Zilog, you have given me a life skill.

  • Saw it coming.. (Score:2, Insightful)

    by Prizm ( 52977 )
    I'm from Nampa, ID, just down the road from the Nampa Zilog-manufacturing plant. I can't say that i didn't see huge losses coming from this company, although the bankruptcy surprised me.

    Zilog has had problems finding a niche for quite some time. In recent years (months?), they have been highly influenced by the market trends, which have affected their product directions. I mean, their main product as of recent is a z80 webserver kit.

    I still think there's plenty of room in the market for a microcontrollers company, but this company needs some serious restructuring. Along those same lines, they need to keep their logos for more than a month at a time. Every time I drive by the plant they have a new logo and coloring scheme, the most recent of which is a horrid yellow-on-purple. You haven't seen tacky until you've seen a beautiful, white, futuristic-looking technology building with a giant yellow 'Z' plastered on the front, covering all the windows.

    Should have seen this bankrupty coming from that alone!

  • What about the other stuff? (Score:5, Interesting)

    by Amazing Quantum Man ( 458715 ) on Friday December 07, 2001 @01:43PM (#2671856) Homepage
    Man, lots of fond reminiscing here about the Z80 (and clones). Quite rightly, too... the Z80 was a fun little beast.

    Zilog, however, made lots of other stuff. Some were moderately successful (Z8530 SCC), some not so (Z8000 MPU).

    The Z8000 actually was fairly popular in military applications until COTS took over. I seem to recall many avionics systems used it. When it came out, it was comparable to the 68K.

    It had 16 16bit registers (r0-r15), each of which could be addressed as 2 8-bit registers (rhN, rlN). R15 was the stack pointer. Nice orthagonal instruction set, with logical block moves (similar to the Z80 LDIR instruction), as compared to the intel REP instructions...

    The registers could be doubled up into 32-bit registers (rr0, rr2, ... rr14). The Z8001 and Z8003 were "segmented", but they used a reasonable segmentation model to achieve 8M memory...

    The low 16 bits were the offset in the segment, and the high 7 bits were the segment number. So, you essentially had 23 bit addressing. Of course, the way you generated segmented addresses was a tad odd... I believe bits 30:24 were the segement number in a 32-bit address.

    Only problem was, they never got the Z8070 FPU working. Bummer.
    • Actually, the Z8000 was a 16-bit machine closer to the PDP-11. It had almost exactly the same addressing limitations as a PDP-11. Zilog's thinking was that they were building a cheaper PDP-11, not realizing that that era was almost over.

      I ported 3COM's UNET TCP/IP stack to an Onyx Z8000 box around 1982. This may have been the first single-chip microprocessor on the Internet. It was at IP address [128.5.32.5]. Note that that's class B network #5; this was early stuff.

    • ... of my first time to the NCC, in the early '70s - when Zilog had first announced the Z8000.

      One of the things I did was drop by the Zilog booth - twice (the second time when the head of the project was there), to comment on the instruction set. Went something like this:

      Me: ~"This is a really great instruction set. But there's one thing missing. When an instruction is aborted by an external memory controller and the interrupt taken, the state isn't preserved well enough to restart the instruction after the memory fault is fixed. You could do true virtual memory if you fixed that.~"

      Him: ~"We're not planning to do that. We already looked at it, and it would expand the microcode by about 50%~"

      Me: ~"Oh, good. Then (given Moore's law improvements in silocon fabrication) it could be done in 6 to 9 months.~"

      Him: ~"Nobody would ever want to do virtual memory on a microprocessor.~"

      So they didn't do it. And a few years later the Motorola 68000 family (which DID have restartable instructions on memory faults) became the canonical processor for the "cheap unix box" explosion.
      • And a few years later the Motorola 68000 family (which DID have restartable instructions on memory faults) became the canonical processor for the "cheap unix box" explosion.

        Motorola didn't support continuation/restart on the original 68000. That was added in the 68010. There was a kludge that some computers used, it involved running two 68000s in lock step, letting one CPU detect the fault and using the other CPU to recover.

  • Holly: I was in love once - a Sinclair ZX-81. People said, "No, Holly, she's not for you." She was cheap, she was stupid and she wouldn't load - well, not for me, anyway.

    Lister: What are you trying to say, Hol?

    Holly: What I'm saying, Dave, is that it's better to have loved and to have lost than to listen to an album by Olivia Newton-John.

    Cat: Why's that?

    Holly: Anything's better than listening to an album by Olivia Newton-John.

  • The cool thing about the Z80 (Score:3, Informative)

    by frank_adrian314159 ( 469671 ) on Friday December 07, 2001 @02:00PM (#2671947) Homepage
    ... was the dual register set. It was used to good advantage in embedded systems where the executive would use one set and the app would use the other. If you remember the chess program Sargon, it used one set for white's state and one for black's. It was a pretty neat machine. But like many of the 8-bit stuff out there, it didn't make the jump to 16 bits gracefully. The Z8000 was pretty dismal...
  • Maybe now the Z80 is just for embedded devices. But from about 1980-1984, I worked at a place that sold Z80-based word-processors (when a 'word-processor' was a physical box). We had all the usual features for that era, such as footnotes, spell-checking, mail-merge, and even a builtin spreadsheet.

    And it was all written in hand-coded assembler.

  • Sad (Score:2, Interesting)

    by John Jorsett ( 171560 )
    I'm one of those veterans who built his own computer at the dawn of the Personal Computer era. The 4 MHz Z80 was the ne plus ultra of the processor world, and we thought we were hot stuff when we managed to overclock one above 5 MHz. Their Serial I/O chips were also the most advanced thing going for serial comms, and we implemented many protocols like X.25 and PARS that formerly required a complete circuit board for what the SIO did. It's a bit sad to see what was once the cutting edge company brought so low.

    • Re:Sad (Score:2)

      by lhand ( 30548 )
      Yea, I really lusted for one of those Z80's in my Imsai 8080 system (2200 solder conections on the motherboard alone, yikes). I finally got one when I installed a floppy controller (Jade) which had one on board. It always seemed weird that my main cpu was a 2 MHz 8080A while my floppy disk controller used a 4 MHz Z80.

      Well, I finally upgraded to the Z80 processor board about a year later and got to start playing with all those cool new instructions. Way cool.

      Hope you get it together, Zilog!
  • My 1985 IBM XT has a disk controller (presumably ESDI?) with a Z80 to run it, in the same way that 68000-series chips show up on RAID cards nowadays. (our mailserver at work has a disk controller more powerful than an Atari TT :) )

Slashdot Top Deals

You are always doing something marginal when the boss drops by your desk.

Close