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Eat your heart out amateur computer builders. Meet the Megaprocessor! - Page 2 — Parallax Forums

Eat your heart out amateur computer builders. Meet the Megaprocessor!

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  • Heater.Heater. Posts: 21,230
    edited 2017-05-10 23:58
    Yeah, who'd want a Monster 8085?
  • MikeDYurMikeDYur Posts: 2,176
    edited 2017-05-10 22:48
    Heater. wrote: »
    What I really want is a scaled up 70's style red LED. No idea how I might make such a thing. Then the idea grows. I'll need giant resistors and capacitor to go around it in a simple flasher circuit and a giant 9v battery!

    The idea of giant resistors and capicitors on a grand scale, can it be done?

    The LED could be done in acrylic. And use a high brightness LED, as long as you don't need a driver. The battery goes without saying.

    Anybody built a custom resistor or capacitor?

    BTW: It's got to look like the real thing only bigger.
  • @heater.,

    paint a coffee-can, beer-can, whatever size you need and put a normal capacitor inside?

    Enjoy!

    Mike
  • Cluso99Cluso99 Posts: 18,066
    Could use 2N3055 TO-52 transistors and 5W resistors and 250V monoblock capacitors ;)
  • Heater. wrote: »
    Yeah, who'd want a Monster 8085?
    Oh - I wasn't thinking of it in that way. Intel did a fair amount of work for the 4004 35th (or was it 45th?) anniversary and that's smaller than a 6502.

    And there's this for the Russian 8080 clone which must have been based on a reverse engineered 8080.
  • Anybody have one of these:
    http://www.kswichit.com


    I have been looking at them for a couple years now, and thought that may be one of the cheapest ways to go retro. Now to figure out what processor has the most bang for the buck, possibly the Z80 or 6502.
    900 x 926 - 226K
  • Looks like kswichit has an eBay store with these kits:

    http://www.ebay.com/usr/kswichit?_trksid=p2047675.l2559

    I don't know about bang for the buck. For me it would me more about nostalgia and would have to be a 6502 or Z80 due to my first exposure to computers being the KIM-1 (dad had it, but I don't remember really using it), Atari 800, and TRS-80 Model III.
  • They posted a video about the monster 6502.:

    http://www.evilmadscientist.com/2017/monster-6502-video/

    I wonder what's in the little box that they plugged it into?
  • KeithE wrote: »
    Looks like kswichit has an eBay store with these kits:

    http://www.ebay.com/usr/kswichit?_trksid=p2047675.l2559

    I don't know about bang for the buck. For me it would me more about nostalgia and would have to be a 6502 or Z80 due to my first exposure to computers being the KIM-1 (dad had it, but I don't remember really using it), Atari 800, and TRS-80 Model III.
    Too bad there isn't one with a 6809.

  • Heater.Heater. Posts: 21,230
    Ah, the 6809. What a wonderful device. The peak of 8 bit micro-processor development. I have fond memories of building up a 6809 board, wire-wrap and all. Writing a debug monitor for it.

    Soon overrun by the arrival of the 68000 and the 8086.

    Ah well.

  • MikeDYurMikeDYur Posts: 2,176
    edited 2017-05-16 13:19
    KeithE wrote: »
    I wonder what's in the little box that they plugged it into?


    I can only speculate, but it must be RAM, ROM and keyboard interface. A pin for pin swap out of the processor in a working system. Looks like an easy way of loading programs into the Monster 6502. And to think their newest revision has even more blinkys.


    I'll take a kit, even if it takes a month to put together.

    What machines had a 6809 in them? I don't recall that processor, it must have had a short life in popularity.


    TRS-80 no less,
    I had to look it up:

    https://en.m.wikipedia.org/wiki/Motorola_6809

    A lot of first's:
    The 6809 was the first microprocessor able to use fully position-independent, or reentrant, or both, code without the use of difficult programming tricks. It also contained one of the first hardware-implementations of a multiplication instruction in an MPU, full 16-bit arithmetic, and an especially fast interrupt system.
  • kwinnkwinn Posts: 8,697
    edited 2017-05-16 13:52
    MikeDYur wrote: »
    ..............

    What machines had a 6809 in them? I don't recall that processor, it must have had a short life in popularity.

    TRS-80 no less,
    I had to look it up:

    https://en.m.wikipedia.org/wiki/Motorola_6809

    A lot of first's:

    The 6809 was the first microprocessor able to use fully position-independent, or reentrant, or both, code without the use of difficult programming tricks. It also contained one of the first hardware-implementations of a multiplication instruction in an MPU, full 16-bit arithmetic, and an especially fast interrupt system.

    It was a great chip, and a joy to program, particularly in assembler. Unfortunate that it came so late on the scene. By the time it came out the early 8 bitters were entrenched in the market and the 16 bitters were starting to be available.
  • TorTor Posts: 2,010
    edited 2017-05-18 07:50
    TRS-80 Color Computer(CoCo), v1, v2, v3, the latter one you could until recently buy refurbished. Great box. Then there were the Dragon 32 and the Dragon 64, British near-clones of the CoCo.
    Hitachi came up with an improved version of the 6809, the HD6309. Unfortunately production of the 6809 and 6309 stopped early, unlike the 65C02 and Z80 which are still in production. But the 3.5MHz HD63C09 runs reliably at 5MHz, reportedly. I have a couple of them in the drawer, for a future project.

    [edit:Fixed typo]
  • Tor wrote: »
    TRS-80 Color Computer(CoCo), v1, v2, v3, the latter one you could until recently buy refurbished. Great box. Then there were the Dragon 32 and the Dragon 64, British near-clones of the CoCo.
    Hitachi came up with an improved version of the 6809, the HD6309. Unfortunately production of the 6809 and 6309 stopped early, unlike the 65C02 and Z80 which are still in production. But the 3.5MHz HD63C09 runs reliably at 5MHz, reportedly. I have a couple of the in the drawer, for a future project.
    I didn't realized that the 6809 was no longer available. I guess that explains why there aren't hobbyist kits to build 6809 computers.
  • KeithEKeithE Posts: 957
    edited 2017-05-16 18:18
    That reminds me - if Heater is back in August...

    http://vcfed.org/wp/festivals/vintage-computer-festival-west/

    I've never been there - did stop by once to donate an Apple II.
  • Heater.Heater. Posts: 21,230
    Wow, KeithE, that sounds like a great happening.

    It's looking unlikely that I'm here in August. But you never know...
  • KeithEKeithE Posts: 957
    edited 2017-05-16 20:11
    MikeDYur wrote: »
    KeithE wrote: »
    I wonder what's in the little box that they plugged it into?
    I can only speculate, but it must be RAM, ROM and keyboard interface. A pin for pin swap out of the processor in a working system. Looks like an easy way of loading programs into the Monster 6502. And to think their newest revision has even more blinkys.

    I was wondering if a Propeller might be in there. Something is doing video generation. At first I thought that they would emulate a particular vintage platform, but maybe it's wholly their creation. When I searched for "Mars Templar" this post came up which looks like a recent creation no?

    http://herculeanpixel.com/news/mars-templar

    Maybe I'll just ask ;-)

    Edited to add: I wonder if they would sell the computer "we have built up a single-board computer (a tiny motherboard) that uses the 6502 as its CPU, such that you can either use a socketed (vintage) 6502 IC, or the MOnSter 6502 through a cable." to help fund the Monster PCB development? Or enable developers?
  • They responded:
    The computer uses an ARM-based microcontroller to emulate a standard set of computer peripheral ICs. Eric has put up a separate blog post where he gives a few more details about its capabilities. And yes, it is likely to evolve into a future product for us. It’s getting to be a wonderful little 6502 development environment, and the fact that you can swap out the IC for the MOnSter is icing on the cake. :)
    And from: http://tubetime.us/index.php/2017/05/16/new-monster6502-updates-with-video/
    The computer I’ve designed for it uses another microcontroller to simulate hardware peripherals, inspired by capabilities of various ’80s computers and gaming consoles. The idea is to offload CPU-intensive video and sound tasks to the microcontroller, freeing up the 6502 so that it can be used in real time despite the slow clock.

    Right now, I’ve implemented several software-defined peripherals

    VGA video output with 256 color graphics, tiles, and sprites
    Multichannel stereo sound synthesizer
    PS/2 keyboard interface
    KIM-1 style front-panel debugging keypad and LED display
    USB-CDC interface with a 6502-accessible UART for communications with a host PC
    The computer can also run a full validation suite on the connected 6502, which has been quite useful troubleshooting the highly complex MOnSter6502 boards.

    The computer is still a prototype, but you can see some shots of it in the video above.
  • I think it was Cluso99 that has aspirations of building a computer out of discrete TTL 7400 logic chips.

    This guy has an ongoing project that is looking nice:

    https://leo1cpu.wordpress.com/

    http://leo1cpu.puntett.net/main.htm
  • Cluso99Cluso99 Posts: 18,066
    edited 2017-05-29 20:48
    MikeDYur wrote: »
    I think it was Cluso99 that has aspirations of building a computer out of discrete TTL 7400 logic chips.

    This guy has an ongoing project that is looking nice:

    https://leo1cpu.wordpress.com/

    http://leo1cpu.puntett.net/main.htm

    Yes, it was me.

    I decided to first start with micros simulating each block/board of logic. Guess what, a prop suited perfectly. I have the monitor leds setup using a 128*128 Color LCD. This saves having to put leds on each board. Each cog will operate autonomously on the bus (I/O) performing one block of the CPU.

    This is currently on hold while I am away in the UK visiting our daughter and family. Thought I may have some time while here, but not yet.

    Once this is working and I am happy, I think I will make up the design in logic, one board for each section. But I will be cheating a bit as I plan to use 74LVC1Gxxx SMT gates and 74LVCxxx 8-bit latches/buffers/etc.

    I often think I would like to build a computer modelled after my first mini-computer, using 74LVCxxx SMT logic. My first mini (a Friden/Singer/ICL System Ten) was purchased 18 months old in 1977. It was the length of my garage, which is where it was housed, after lining the walls etc plus appropriate air conditioning and power. I maintained it fully operational until 2000 when I sold it for scrap (gold value on the contact).
  • jmgjmg Posts: 15,140
    Cluso99 wrote: »
    Once this is working and I am happy, I think I will make up the design in logic, one board for each section. But I will be cheating a bit as I plan to use 74LVC1Gxxx SMT gates and 74LVCxxx 8-bit latches/buffers/etc...

    If you are going to do one board for each section, why not drop a modest FPGA/CPLD onto a board, then you can recode/revise each section easily ?
    Use an external JTAG card to update them, to keep the boards compact.

    eg I see iCE40 series in QFN packages start at
    QFN32, $1.27/100 with 21io,
    QFN48 gives 39io, and ranges from $3.29/100 to $6.30, and have 8kB ~ 128kB RAM

    They also have gull wing parts, of 100,144 pins, but you seem less likely to be io limited

    The MachXO2 packs a little more into QFN32, with 21io, 1280LE and 8kB RAM, but at a higher price point of $4.77/100
    iCE40 give more logic/$, but they need external Flash and core Vcc.
  • Cluso99Cluso99 Posts: 18,066
    jmg wrote: »
    Cluso99 wrote: »
    Once this is working and I am happy, I think I will make up the design in logic, one board for each section. But I will be cheating a bit as I plan to use 74LVC1Gxxx SMT gates and 74LVCxxx 8-bit latches/buffers/etc...

    If you are going to do one board for each section, why not drop a modest FPGA/CPLD onto a board, then you can recode/revise each section easily ?
    Use an external JTAG card to update them, to keep the boards compact.

    eg I see iCE40 series in QFN packages start at
    QFN32, $1.27/100 with 21io,
    QFN48 gives 39io, and ranges from $3.29/100 to $6.30, and have 8kB ~ 128kB RAM

    They also have gull wing parts, of 100,144 pins, but you seem less likely to be io limited

    The MachXO2 packs a little more into QFN32, with 21io, 1280LE and 8kB RAM, but at a higher price point of $4.77/100
    iCE40 give more logic/$, but they need external Flash and core Vcc.
    I could build the whole device in an fpga. I have said before, that's not what I want to do. I have designed commercial products with fpgas some years ago.
    If I used an fpga I would be building a big retro mini-computer, which might even be my own design. But that's not my current interest.
  • Really awesome, something I wish I (and every kid) could have seen back in school. Would help with the understanding of what's going on under the hood!
  • Say I can build an extremely simple microprocessor with 1600 BJT transistors. This would basically be a square grid of 40 x 40 transistors. TO-92 transistors for visual appeal, this should fit on a PC board 6" square. This is a nice size for a really cool coffee table display, like the 555 board. But even better, because it will be one monolithic grid of black transistors, intersped with 50 or so LEDs. (all resistors will be on underside of board)

    The transistors should be well under 20 cents each, otherwise project will be getting too expensive.

    Question: My understanding is that there are no single FET transistors available in a TO92-like package. Is this correct?
  • kwinnkwinn Posts: 8,697
    The_Master wrote: »
    Say I can build an extremely simple microprocessor with 1600 BJT transistors. This would basically be a square grid of 40 x 40 transistors. TO-92 transistors for visual appeal, this should fit on a PC board 6" square. This is a nice size for a really cool coffee table display, like the 555 board. But even better, because it will be one monolithic grid of black transistors, intersped with 50 or so LEDs. (all resistors will be on underside of board)

    The transistors should be well under 20 cents each, otherwise project will be getting too expensive.

    Question: My understanding is that there are no single FET transistors available in a TO92-like package. Is this correct?

    Lots available, see http://www.mouser.com/Semiconductors/Discrete-Semiconductors/Transistors/MOSFET/_/N-ax1sf?P=1z0y3jsZ1z0y3zr
  • That's really cool! I love builds where you can see the builder's passion for their project. I could just stare at those blinking leds on the memory module all day!
  • I've built a few of these SN series flip flop cpu's loading the code with address dip or toggle switches get's old quick. Easier to write to the memory with a arduino etc.
  • The relay cpu is also interesting the along with it's cricket sounding noise
  • KeithEKeithE Posts: 957
    edited 2017-06-02 17:21
    Andrew Holme turned the Visual6502 netlist into Verilog that can be synthesized and loaded into an FPGA:

    http://www.aholme.co.uk/6502/Main.htm

    This might be a good reference model for anyone verifying their own more efficient 6502 core.

    He's got a lot of projects on his page including a homemade GPS, and computers built from discrete logic.

    Edited to add: this page may be of interest to 6502 programmers too, especially if they had an Atari VCS - http://8bitworkshop.com/?platform=vcs&file=examples/hello
  • Monster 8080: "8080 CPU, built entirely by DTL-technology"

    http://lovqvist.net/8080/index.html
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