7 ms·

Die photos and analysis of the revolutionary 8008 microprocessor, 45 years old

256 points by kens 10y ago

indexerror 10y ago
Very cool. I wish university professors use this article as a precursor to the computer architecture course material. Its much more interesting to study something when you have a historical perspective that you can relate to later on in the course.
- ilogik 10y ago
  my microprocessor course in college was actually based on the 8008 (or something similar). We laughed about it that it was old, but pretty much everything still applies in today's micocontrollers
  - Roboprog 10y ago
    Z80, back in the mid 80s.
ChuckMcM 10y ago
Very cool, as I recall the 8080 needed multiple power supplies and a clock generator and the 8080A made those internal to the chip. The Z80 was usable with no support chips at all and I believe that was the primary motivation for the 8085. When you look that notion of the 8238 you can see the seeds of the 'south bridge' that was so prevalent in PC design. Intel systems broke apart as "memory" (northbridge), "compute" (cpu), and "i/o" (southbridge). That has been a pretty successful architecture and one that ARM would do well to emulate for their non-SoC offerings.
SN76477 10y ago
Thanks, looks like a great read.
ilogik 10y ago
I like how similar the Vcc and GND lines are to the circulatory system (arteries and veins), especially with those colors
- dom0 10y ago
  In ye-olde planar layouts (TTL-era) they were routed quite similar, like arteries and veins, with small 100n caps and the TTL chips as a sort of capillaries. However, this kind of power supply routing (not sure Am. call it idiomatically, some here call it a "ladder supply/layout") has poor electrical properties, unsuitable to operating logic beyond a couple MHz.
kibwen 10y ago
Despite how simple the 8008 is compared to modern processors, I wonder if we'll ever see some sort of commercially-available "3D printer for circuits" that would be able to reproduce something of its caliber. Such a thing would finally enable truly open computing at every level, which, even if far less capable than high-end processors, would be sufficient for lots of tasks.
- rpearl 10y ago
  The processes needed to fabricate silicon are more subtractive than additive.
  - kibwen 10y ago
    It someone wants to invent a microscale CNC machine to make it happen, I won't complain. :)
- yaakov34 10y ago
  You can easily replicate a 4000-transistor microprocessor with the lowest-end FPGA for a few dollars - cheaper than any 3D-printing process for silicon that I can imagine. It would, of course, also be reprogrammable, making it very cheap for prototypes and experiments.
  - kibwen 10y ago
    From a security perspective, how feasible is it for a state-level actor to usefully backdoor a FPGA? I imagine that part of the appeal of personally-fabricated hardware is that, if you validate the design, you have greater assurance about the code executing on your machine. Sort of like the difference between compiling from source and trusting a binary blob (though, just like compilers can be backdoored, I imagine there are theoretical attacks involving subverting the fab itself...).
    - yaakov34 10y ago
      Sure. FPGAs, or any IC, could contain subversive/backdoor hardware placed there by a sophisticated actor. For that matter, so could ostensibly passive components like connectors, ports, flat ribbon cables... now that we have sophisticated circuits that can be powered by stray magnetic waves (RFID and its advanced friends), so can components not connected to power, such as cases, clips, screws. It is a fascinating thing to think about, actually, and I don't see how 3D-printing every single thing around you is a realistic solution. And considering that regular color printers (inkjet and laser) have all been backdoored for ages - they print mostly invisible constellations of dots into every page which identify the individual printer - I would say that backdooring a "silicon printer" is also a definite possibility.
contingencies 10y ago
Not directly related but just last week I just gifted two Intel 8088 machines including one in a really beautiful case with original "3 year warranty!" sticker, along with other stuff (period disks, Apple LCII, Apple II, SGI/SunOS/Solaris stuff, etc.) to http://acms.org.au/ http://acms.org.au/ who are looking for an exhibition location for their huge collection. As a registered charity, space donations are tax deductible and can help meet council public space/cultural requirements for new developments. Requirements: Sydney or Canberra, 100-300m2 exhibition space (really 200+), 500-1000m2 storage space (500+ already in use).
- watersb 10y ago
  Thank you for doing this. In 2011, I donated a mass of Mac computers to a podcaster who wanted to set up a museum of Mac history. It was a lot of work. Not news to the HN readers, but yeah: computers used to be even more difficult to use than they are now. And of course getting all of the bits together for a working system takes a lot of time.
userbinator 10y ago
The instruction encoding of the 8008 is best seen in octal, like its successors, which makes it quite easy to decode: http://pastraiser.com/cpu/i8008/i8008_opcodes.html http://pastraiser.com/cpu/i8008/i8008_opcodes.html 1/4 of the opcode space is moves and 1/4 is ALU ops. It is quite RISC-like in its simplicity, although it does contain memory-register ops.
- kens 10y ago
  Most of the time octal causes me pain, but octal is definitely the way to understand Intel instruction sets. In hex you can sort of see some patterns, but in octal things are trivial. The octal encoding goes back to the Datapoint 2200, which use BCD decoder chips (7442) for instruction decoding. These were used to decode three instruction bits at a time, so the instruction set of the Datapoint 2200 (and thus the 8008) was based on groups of three bits. Among other things, that's why the 8008 has 7 registers (A, B, C, D, E, H, L) - the 8th value was used to indicate a memory access. Also see "x86 is octal": http://www.dabo.de/ccc99/www.camp.ccc.de/radio/help.txt http://www.dabo.de/ccc99/www.camp.ccc.de/radio/help.txt
Aardwolf 10y ago
Is there a diagram of this CPU or similar available which is at the logic gate level rather than transistors? Thanks! :)
- gregsadetsky 10y ago
  Great question! I found this after a bit of searching: http://www.cs.princeton.edu/courses/archive/fall09/cos126/lectures/22CPU-2x2.pdf http://www.cs.princeton.edu/courses/archive/fall09/cos126/le... (see next to last page)
WestCoastJustin 10y ago
Can anyone recommend a few books on chip manufacturing? I am completely blown away at the scale they are working with here. I'm particularly interested in a "how it's made" type book. This is obviously something that requires significant upfront investment. The scale makes this seem so difficult. I'm a total newb is this area so I might not even be asking the right questions yet.
- abecedarius 10y ago
  Back in the 80s I took a freshman lab course on this at Caltech. The course notes were available at the campus bookstore, but I don't think they were ever a proper book with an ISBN (and I hope there's something newer, though maybe there's not much new to say about the kind of crude small-scale ICs we got to make in the lab).
intrasight 10y ago
When I was a teen, my older brother loaned me his copy of the book "State of the Art : A Photographic History of the Integrated Circuit" which included a die photo of the 8008. And thus began my love affair with computers.

256 points by kens 10y ago

Very cool. I wish university professors use this article as a precursor to the computer architecture course material. Its much more interesting to study something when you have a historical perspective that you can relate to later on in the course.

ilogik 10y ago
my microprocessor course in college was actually based on the 8008 (or something similar). We laughed about it that it was old, but pretty much everything still applies in today's micocontrollers
- Roboprog 10y ago
  Z80, back in the mid 80s.

ChuckMcM 10y ago

Very cool, as I recall the 8080 needed multiple power supplies and a clock generator and the 8080A made those internal to the chip. The Z80 was usable with no support chips at all and I believe that was the primary motivation for the 8085. When you look that notion of the 8238 you can see the seeds of the 'south bridge' that was so prevalent in PC design. Intel systems broke apart as "memory" (northbridge), "compute" (cpu), and "i/o" (southbridge). That has been a pretty successful architecture and one that ARM would do well to emulate for their non-SoC offerings.

SN76477 10y ago

Thanks, looks like a great read.

ilogik 10y ago

I like how similar the Vcc and GND lines are to the circulatory system (arteries and veins), especially with those colors

dom0 10y ago
In ye-olde planar layouts (TTL-era) they were routed quite similar, like arteries and veins, with small 100n caps and the TTL chips as a sort of capillaries. However, this kind of power supply routing (not sure Am. call it idiomatically, some here call it a "ladder supply/layout") has poor electrical properties, unsuitable to operating logic beyond a couple MHz.

kibwen 10y ago

Despite how simple the 8008 is compared to modern processors, I wonder if we'll ever see some sort of commercially-available "3D printer for circuits" that would be able to reproduce something of its caliber. Such a thing would finally enable truly open computing at every level, which, even if far less capable than high-end processors, would be sufficient for lots of tasks.

rpearl 10y ago
The processes needed to fabricate silicon are more subtractive than additive.
- kibwen 10y ago
  It someone wants to invent a microscale CNC machine to make it happen, I won't complain. :)
yaakov34 10y ago
You can easily replicate a 4000-transistor microprocessor with the lowest-end FPGA for a few dollars - cheaper than any 3D-printing process for silicon that I can imagine. It would, of course, also be reprogrammable, making it very cheap for prototypes and experiments.
- kibwen 10y ago
  From a security perspective, how feasible is it for a state-level actor to usefully backdoor a FPGA? I imagine that part of the appeal of personally-fabricated hardware is that, if you validate the design, you have greater assurance about the code executing on your machine. Sort of like the difference between compiling from source and trusting a binary blob (though, just like compilers can be backdoored, I imagine there are theoretical attacks involving subverting the fab itself...).
  - yaakov34 10y ago
    Sure. FPGAs, or any IC, could contain subversive/backdoor hardware placed there by a sophisticated actor. For that matter, so could ostensibly passive components like connectors, ports, flat ribbon cables... now that we have sophisticated circuits that can be powered by stray magnetic waves (RFID and its advanced friends), so can components not connected to power, such as cases, clips, screws. It is a fascinating thing to think about, actually, and I don't see how 3D-printing every single thing around you is a realistic solution. And considering that regular color printers (inkjet and laser) have all been backdoored for ages - they print mostly invisible constellations of dots into every page which identify the individual printer - I would say that backdooring a "silicon printer" is also a definite possibility.

contingencies 10y ago

Not directly related but just last week I just gifted two Intel 8088 machines including one in a really beautiful case with original "3 year warranty!" sticker, along with other stuff (period disks, Apple LCII, Apple II, SGI/SunOS/Solaris stuff, etc.) to http://acms.org.au/ http://acms.org.au/ who are looking for an exhibition location for their huge collection. As a registered charity, space donations are tax deductible and can help meet council public space/cultural requirements for new developments. Requirements: Sydney or Canberra, 100-300m2 exhibition space (really 200+), 500-1000m2 storage space (500+ already in use).

watersb 10y ago
Thank you for doing this. In 2011, I donated a mass of Mac computers to a podcaster who wanted to set up a museum of Mac history. It was a lot of work. Not news to the HN readers, but yeah: computers used to be even more difficult to use than they are now. And of course getting all of the bits together for a working system takes a lot of time.

userbinator 10y ago

The instruction encoding of the 8008 is best seen in octal, like its successors, which makes it quite easy to decode: http://pastraiser.com/cpu/i8008/i8008_opcodes.html http://pastraiser.com/cpu/i8008/i8008_opcodes.html 1/4 of the opcode space is moves and 1/4 is ALU ops. It is quite RISC-like in its simplicity, although it does contain memory-register ops.

kens 10y ago
Most of the time octal causes me pain, but octal is definitely the way to understand Intel instruction sets. In hex you can sort of see some patterns, but in octal things are trivial. The octal encoding goes back to the Datapoint 2200, which use BCD decoder chips (7442) for instruction decoding. These were used to decode three instruction bits at a time, so the instruction set of the Datapoint 2200 (and thus the 8008) was based on groups of three bits. Among other things, that's why the 8008 has 7 registers (A, B, C, D, E, H, L) - the 8th value was used to indicate a memory access. Also see "x86 is octal": http://www.dabo.de/ccc99/www.camp.ccc.de/radio/help.txt http://www.dabo.de/ccc99/www.camp.ccc.de/radio/help.txt

Aardwolf 10y ago

Is there a diagram of this CPU or similar available which is at the logic gate level rather than transistors? Thanks! :)

gregsadetsky 10y ago
Great question! I found this after a bit of searching: http://www.cs.princeton.edu/courses/archive/fall09/cos126/lectures/22CPU-2x2.pdf http://www.cs.princeton.edu/courses/archive/fall09/cos126/le... (see next to last page)

WestCoastJustin 10y ago

Can anyone recommend a few books on chip manufacturing? I am completely blown away at the scale they are working with here. I'm particularly interested in a "how it's made" type book. This is obviously something that requires significant upfront investment. The scale makes this seem so difficult. I'm a total newb is this area so I might not even be asking the right questions yet.

abecedarius 10y ago
Back in the 80s I took a freshman lab course on this at Caltech. The course notes were available at the campus bookstore, but I don't think they were ever a proper book with an ISBN (and I hope there's something newer, though maybe there's not much new to say about the kind of crude small-scale ICs we got to make in the lab).

intrasight 10y ago

When I was a teen, my older brother loaned me his copy of the book "State of the Art : A Photographic History of the Integrated Circuit" which included a die photo of the 8008. And thus began my love affair with computers.