6 ms·

There's also the MOnSter 6502, an exact copy of the 6502 microprocessor built with discrete transistors on a 12"x15" board. It's operational and Apple Integer B

by kens 10y ago

There's also the MOnSter 6502, an exact copy of the 6502 microprocessor built with discrete transistors on a 12"x15" board. It's operational and Apple Integer Basic runs successfully on it, slightly slower than the real chip. It's quite impressive, since unlike the real processor, the MOnSter 6502 has a bunch of LEDs indicating the internal state. See http://monster6502.com/ http://monster6502.com/

anexprogrammer 10y ago
I'd forgotten with current 1bn transistor counts that it ran with just 4k! See http://www.visual6502.org http://www.visual6502.org for a great visual sim of a chip operating.
AceJohnny2 10y ago
The best part about the MOnSter 6502 is you can control the frequency through a potentiometer :) A really excellent way to switch between actually seeing the individual instructions being decoded and executed and getting something fast enough to be (barely) usable!
- userbinator 10y ago
  What's really attractive to me is that it's also an existing, "real" architecture instead of a custom one-off (which may have been designed specifically to ease a particular implementation.) It would be fun to see a discrete 8080, Z80, or even 8086, for much the same reason.
  - Retr0spectrum 10y ago
    8080 would probably be doable, but the Z80 has over double the transistor count, so it would be (even more) impractical to construct. The 8086 has an order of magnitude more transistors. Would definitely be very cool to see though.
  - creshal 10y ago
    > which may have been designed specifically to ease a particular implementation To be fair, so are all the "real" architectures. 8-bit chips especially are nothing but trade-offs to keep transistor count down.
  - Animats 10y ago
    The first generation DEC PDP-8 minicomputer was a discrete-component machine the size of a small refrigerator.[1] Probably the smallest pre-IC computer manufactured. [1] https://en.wikipedia.org/wiki/PDP-8 https://en.wikipedia.org/wiki/PDP-8
    - inetsee 10y ago
      My very first job after graduating college was working with a PDP-8. At one point we had a hardware failure. We had a maintenance contract, so DEC sent out an engineer. After confirming the fault from the diagnostics I had run, he pulled a circuit board out, unsoldered a transistor, and soldered in a new one. We also upgraded the hardware while I worked there. We doubled the memory from 4K words (6K bytes) to 8K words. The upgrade cost five thousand dollars.
    - kens 10y ago
      The smallest pre-IC computer is probably an aerospace computer. These computers are very interesting, but almost totally neglected. For instance, in 1960 Atlas ICBMs (nuclear missiles) were guided by a computer that was a two foot cube and weighed 240 pounds. Side note: PROM memories were invented for this computer, so missiles could be aimed at different targets in the field. In 1962, Arma created the first microcomputer, or at least the first computer with that name. The Arma Micro Computer was a general-purpose aerospace computer built from transistors and transfluxors (two-hole core memory with a cool name). The computer was a tiny 0.4 cubic feet and 20 pounds. It was a 22-bit machine; while we now think word sizes must be a power of 2, back then people used whatever word size gave them the accuracy they needed.
      - Animats 10y ago
        The original Atlas guidance computer was ground-based.[1] It was the first transistorized computer, but it was a sizable mainframe and not on the missile. Guidance was by radio control. The ARMA Micro D is really obscure. It shows up in some lists of early computers. Apparently it was inside some versions of the LTN-51 inertial navigation system.[2][3] But this seems to have been around 1969-1970. The Concorde used that navigation system. [1] http://afspacemuseum.org/displays/BurroughsComputer/Burroughs_Historical_Summary.pdf http://afspacemuseum.org/displays/BurroughsComputer/Burrough... [2] https://www.flightglobal.com/FlightPDFArchive/1970/1970%20-%200479.PDF https://www.flightglobal.com/FlightPDFArchive/1970/1970%20-%... [3] http://www.seaboardairlines.org/aircraft/ins-2.htm http://www.seaboardairlines.org/aircraft/ins-2.htm
- Keyframe 10y ago
  Potentiometer is cool, but not as cool as a crank wheel operated clock https://www.youtube.com/watch?v=0GmY_UrbXnA https://www.youtube.com/watch?v=0GmY_UrbXnA
nibnib 10y ago
I think it's actually much slower than the original. >The maximum reliable clock rate is not yet determined, but we expect it to be in the tens to (low) hundreds of kHz.

by kens 10y ago

anexprogrammer 10y ago

I'd forgotten with current 1bn transistor counts that it ran with just 4k! See http://www.visual6502.org http://www.visual6502.org for a great visual sim of a chip operating.

AceJohnny2 10y ago

The best part about the MOnSter 6502 is you can control the frequency through a potentiometer :) A really excellent way to switch between actually seeing the individual instructions being decoded and executed and getting something fast enough to be (barely) usable!

userbinator 10y ago
What's really attractive to me is that it's also an existing, "real" architecture instead of a custom one-off (which may have been designed specifically to ease a particular implementation.) It would be fun to see a discrete 8080, Z80, or even 8086, for much the same reason.
- Retr0spectrum 10y ago
  8080 would probably be doable, but the Z80 has over double the transistor count, so it would be (even more) impractical to construct. The 8086 has an order of magnitude more transistors. Would definitely be very cool to see though.
- creshal 10y ago
  > which may have been designed specifically to ease a particular implementation To be fair, so are all the "real" architectures. 8-bit chips especially are nothing but trade-offs to keep transistor count down.
- Animats 10y ago
  The first generation DEC PDP-8 minicomputer was a discrete-component machine the size of a small refrigerator.[1] Probably the smallest pre-IC computer manufactured. [1] https://en.wikipedia.org/wiki/PDP-8 https://en.wikipedia.org/wiki/PDP-8
  - inetsee 10y ago
    My very first job after graduating college was working with a PDP-8. At one point we had a hardware failure. We had a maintenance contract, so DEC sent out an engineer. After confirming the fault from the diagnostics I had run, he pulled a circuit board out, unsoldered a transistor, and soldered in a new one. We also upgraded the hardware while I worked there. We doubled the memory from 4K words (6K bytes) to 8K words. The upgrade cost five thousand dollars.
  - kens 10y ago
    The smallest pre-IC computer is probably an aerospace computer. These computers are very interesting, but almost totally neglected. For instance, in 1960 Atlas ICBMs (nuclear missiles) were guided by a computer that was a two foot cube and weighed 240 pounds. Side note: PROM memories were invented for this computer, so missiles could be aimed at different targets in the field. In 1962, Arma created the first microcomputer, or at least the first computer with that name. The Arma Micro Computer was a general-purpose aerospace computer built from transistors and transfluxors (two-hole core memory with a cool name). The computer was a tiny 0.4 cubic feet and 20 pounds. It was a 22-bit machine; while we now think word sizes must be a power of 2, back then people used whatever word size gave them the accuracy they needed.
    - Animats 10y ago
      The original Atlas guidance computer was ground-based.[1] It was the first transistorized computer, but it was a sizable mainframe and not on the missile. Guidance was by radio control. The ARMA Micro D is really obscure. It shows up in some lists of early computers. Apparently it was inside some versions of the LTN-51 inertial navigation system.[2][3] But this seems to have been around 1969-1970. The Concorde used that navigation system. [1] http://afspacemuseum.org/displays/BurroughsComputer/Burroughs_Historical_Summary.pdf http://afspacemuseum.org/displays/BurroughsComputer/Burrough... [2] https://www.flightglobal.com/FlightPDFArchive/1970/1970%20-%200479.PDF https://www.flightglobal.com/FlightPDFArchive/1970/1970%20-%... [3] http://www.seaboardairlines.org/aircraft/ins-2.htm http://www.seaboardairlines.org/aircraft/ins-2.htm
Keyframe 10y ago
Potentiometer is cool, but not as cool as a crank wheel operated clock https://www.youtube.com/watch?v=0GmY_UrbXnA https://www.youtube.com/watch?v=0GmY_UrbXnA

nibnib 10y ago

I think it's actually much slower than the original. >The maximum reliable clock rate is not yet determined, but we expect it to be in the tens to (low) hundreds of kHz.