What is this Intel 8080 thing anyway?

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  • Опубліковано 23 сер 2024
  • Intel 8080 CPU, dual Shugart drives, RAM, ROM, and a serial port. It's a computer, right? Well, let's try to figure out what the heck it actually is.
    Twitter: / talesofweird
    Instagram: / talesofweirdstuff
    00:16 Intro
    01:45 System overview
    04:26 External connections
    07:13 Plan to dump the ROMs
    09:58 2708 EPROMs are painful
    12:06 Sketchy 2708 reader
    15:33 The ROM dumps!
    19:51 Closing words
    GitHub repository containing the ROM images:
    github.com/ian...
    A very sketchy way to dump a 2708:
    www.pinwiki.co...
    A less sketchy way to dump a 2708:
    museo.freaknet...

КОМЕНТАРІ • 35

  • @TalesofWeirdStuff
    @TalesofWeirdStuff  Рік тому

    After rewatching the video, I realized that I never said that I verified that the EPROMs are 2708s before attempting to read them as such... and people have rightfully called me out for it. :) I just added a picture to the GitHub repo linked in the description showing that at least one of the chips is a 2708.

  • @tomknowles8979
    @tomknowles8979 Рік тому +12

    I believe it was a "stand alone" disk duplicator. Loved the video!

  • @Arivia1
    @Arivia1 Рік тому +1

    Good luck, here's a like!
    An actual suggestion: you mentioned being in Portland (possibly Oregon)? If you are, Adrian Black is in the area, and he's mentioned in the past that he has an EPROM reader that can handle older chips that do require other voltages. Maybe you could get in touch with him and see if he could try and dump the ROMs in a less hacky method.

    • @TalesofWeirdStuff
      @TalesofWeirdStuff  Рік тому +1

      Adrian and I have met. :) I loaned him an Atari ST that he used in a troubleshooting video back in September 2021.

  • @viscountalpha
    @viscountalpha Рік тому +2

    We do have some veriacs for sale at surplus gizmos for cheap right now which is great for slowly adding power to some of those older power supplies, as you don't want a sudden inrush of current on those caps. The caps likely need to be reformed.

    • @TalesofWeirdStuff
      @TalesofWeirdStuff  Рік тому

      I almost bought a (vintage) variac a couple months ago... I didn't know what I would use it for, and someone else was interested in it. I let the other guy get it. :shrug:

  • @abx42
    @abx42 Рік тому +1

    I've seen some crazy work arounds. But I think this one takes to cake.

    • @TalesofWeirdStuff
      @TalesofWeirdStuff  Рік тому

      No kidding. I will have to build something less sketchy before I try anything like that again.

  • @rager1969
    @rager1969 Рік тому +1

    If it were Adrian, he wouldn't have worried about bending the pins (heck, he'll CUT pins), but he would've done what you did, just because it's easier, especially with 8 of them. I just wouldn't assume any or all of them were 2708. I'd try to trace the sockets to see which pins had power and ground and try to determine what power the PSU would generate. And if they matched the 2708, then I'd be comfortable applying the power and trying to read them.

    • @TalesofWeirdStuff
      @TalesofWeirdStuff  Рік тому

      I Adrian's defense, I've only ever seen him cut pins on chips that he was reasonably sure were already defective. As for the 2708... I just added a picture to the GitHub repo linked in the description showing that at least one of the chips is a 2708.

  • @Plarndude
    @Plarndude Рік тому

    Hello! Have a great night. Stay chill and hydrated.

  • @minombredepila1580
    @minombredepila1580 Рік тому +3

    These P8251 "Asynchronous Serial Controller" and English words in clear in some of the ROMs, making me think that it possibly could work autonomously commanded via the Serial Port and, as @tomknowles8979 suggested could duplicate disks (no point on reading/writing disks via serial with ASCII responses in the ROM). Does this supports dual usage as a floppy drive and duplicator (given the ins1771d-1 that could do both and at least two lines from it go to the P8251 using the Data Access Lines bus, sorry, I cannot see more ) ??? And a big thank you for not bending the pins 😁 BTW, the Retro Chip Tester would read them 😉

    • @TalesofWeirdStuff
      @TalesofWeirdStuff  Рік тому +2

      Yeah... there was no way I was going to bend those pins up on 6 chips and solder wires to them. Madness! I didn't even thing of the Retro Chip Tester. I have one of those, but I think I'm missing the module that lets you dump ROMs to MicroSD. I know some other folks in my area that have all that, so I might borrow it.

  • @beatadalhagen
    @beatadalhagen Рік тому +1

    Try 'xxd' over 'od -t' for initial viewing of dumps, I find it a little easier to spot things at least.

    • @TalesofWeirdStuff
      @TalesofWeirdStuff  Рік тому

      I often forget about that program. Thanks for reminding me. :) I do like the way it mixes hex and ASCII.

  • @viscountalpha
    @viscountalpha Рік тому +1

    I did see something similar or this kind of computer. it was a littleboard, which I ended up selling. it could be a custom job or a kit company that just dried up. 77 was before my time, but I heard it was a very wild west era for personal computing.

    • @TalesofWeirdStuff
      @TalesofWeirdStuff  Рік тому

      That got me thinking... Byte magazine existed back then, and they covered a lot of unusual things. I wonder if this thing might have appeared in some issue of Byte in the 77 - 79 time period.

  • @joetoney184
    @joetoney184 Рік тому +1

    Looks like a line printer interface

    • @TalesofWeirdStuff
      @TalesofWeirdStuff  Рік тому

      It's not impossible... but I would have expected some text in the ROMs related to printing. Maybe those other ROMs didn't dump properly, and there's some missing clues there?

  • @geoffreed4199
    @geoffreed4199 Рік тому +1

    Can read that in vintage data I/o programmers

    • @TalesofWeirdStuff
      @TalesofWeirdStuff  Рік тому

      I've passed up several opportunities to get vintage EPROM programmers because I didn't think they had any utility. Now I know better!

  • @drozcompany4132
    @drozcompany4132 Рік тому +1

    Dude, the pcb only has 2 power wires going to it, so how would it supply +5, -5, and +12 to the EPROMs without some kind of on-board switching supply? I suspect you have 2716s, and hopefully you didn't smoke them with the 12 Volts. Why wouldn't you try that first before being convinced they were 2708s? 2716s came out in like '77 and the tag said 1979 on them.

    • @TalesofWeirdStuff
      @TalesofWeirdStuff  Рік тому

      There are a couple loose wires from the power supply that were presumably connected to the board at one time. I peeled back the label on the ROM labeled 6, and it said 2708 on the chip. I thought that was pretty convincing. :)

    • @TalesofWeirdStuff
      @TalesofWeirdStuff  Рік тому

      @drozcompany4132 I just added a picture to the GitHub repo linked in the description showing that at least one of the chips is a 2708.

  • @DAVIDGREGORYKERR
    @DAVIDGREGORYKERR Рік тому +1

    If you go back and watch your video stream you should be able to figure out which ROM goes where.

    • @TalesofWeirdStuff
      @TalesofWeirdStuff  Рік тому

      About that... :( That was my plan. However, between my camera overexposing and OBS recording at a low bit rate, I can't actually read any of the labels. I can tell which ones are 5 and 6, so I have a guess which order the other are.

  • @orionfl79
    @orionfl79 Рік тому +1

    I cast my vote for it being a stone age word processor. 🐵

    • @TalesofWeirdStuff
      @TalesofWeirdStuff  Рік тому +1

      Like with the suggestion that it might be a printer interface, it's not impossible... but I would have expected some text in the ROMs related to word processing tasks. Maybe those other ROMs didn't dump properly, and there's some missing clues there?

    • @orionfl79
      @orionfl79 Рік тому +1

      @@TalesofWeirdStuff Well, I did say stone age. For example - I've got an old IBM Wheelwriter from 1986 that has some super basic word processing capabilities like saving blocks of text in memory then playing them back with a key combination. But anything is possible! I'm curious to see what it does when you're able to plug in a console and fire it up. ^_^

  • @geneirwin645
    @geneirwin645 Рік тому +1

    You can dump roms with arduino, and it looks like you have a problem with an upper address line causing code duplication.

    • @TalesofWeirdStuff
      @TalesofWeirdStuff  Рік тому

      The EPROM programmer that I was using only had 2716 (2K x 8), so it just read the 1K x 8 ROM twice. I made some updates to the video description... I found an (old!) article about dumping 2708s with a PIC, so I suspect the Arduino circuit would be very similar. I may have to give that a try one of these days too.

  • @chaoticsystem2211
    @chaoticsystem2211 11 місяців тому

    You also need a limiter :D

  • @paulgray1699
    @paulgray1699 Рік тому +2

    Data recorder

    • @TalesofWeirdStuff
      @TalesofWeirdStuff  Рік тому +1

      I'm imaging a flight recorder box where the co-pilot has to change the floppy every few minutes. 🤣