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After my long post last week I thought maybe another one might not be needed. But then this week Cameron unleashed a torrent of technobabble, whiteboarding and wall code that even made me ponder a little. So here's some more explanations and background. As before, I try to provide a general meaning, then a little more detail for the curious.

In addition to these notes, you may want to look at AMC's Story Sync for HACF. It has some episode trivia, polls and other multimedia fun. It's designed to auto-advance while watching the show live, but it mostly works to page through it manually at any time.

OK, so here goes. Comments/corrections/additions welcome.


1983: The show is indeed set in 1983. I thought the show might be about the first company to reverse-engineer the IBM PC BIOS, but it gets established in this episode that they're not the first to do so.

Columbia Data and Compaq: Real-life companies, at that time, mentioned by Joe. These companies reverse-engineered the IBM PC BIOS in 1982. They also used "clean room design" to avoid infringing IBM's copyrights.

CPU: Central Processing Unit. Also known as a microprocessor in the personal computer because it is entirely on a single chip. This is the part of the computer that actually executes the machine-readable instructions of programs. (I define this term here because I had to use it a lot, below.)

Cameron's Quotes and Scribbles

"Sure, I might decide I want to spend the rest of my natural life waiting to move an instruction without a 16-bit bus, ..." -- Cameron speaking to IBM Lawyers

  • The gist: Cameron is insulting IBM's PC hardware and BIOS as being frustratingly slow and inferior. Cardiff Electric's PC will be using a newer CPU with better capabilities, and Cameron's BIOS will support those features.
  • The tech: The data "bus" is the electronic circuitry that transfers data and instructions between where they're stored in memory and where they're executed in the CPU. The IBM PC had a data bus of only 8 bits, which could transfer 8 bits (1 byte) at a time. This doesn't mean the CPU with the 16-bit bus is fully twice as fast, but in this case it's certainly much faster.

"Computers should have photorealistic screens, ... a million pixels, ... and... and..." -- Cameron arguing with Gordon

  • The gist: Cameron is dreaming way beyond her current technology. Regarding graphics: true photorealism and a million pixels on personal computers didn't happen until about ten years later.
  • The tech: Pixels relate to the dots of light that make up an image displayed on the screen. Home computers of 1983 generally could only manage 64,000 pixels (320 horizontal by 200 vertical) using only 4 colors. Photorealism requires at least thousands of colors.

Cameron's big whiteboard

  • The gist: Most of it is useful, very technical details of the CPU that will be used in Cardiff Electric's clone computer.
  • The tech: Across the top is the 16-bit flags register (an internal detail) of the early Intel x86 family of CPUs. In the middle are misc details about x86 commands. At the bottom, oddly, are assembly language's naming rules for labels and values, using a style of specifying patterns called regular expressions.

"... to align on octal boundaries. ... we can do a shift left together with a 3 bit zero fill to the right, which is faster and gives the same results on the accumulator on the 80186...." -- Cameron speaking to Joe.

  • The gist: Cameron is taking time out from writing the BIOS to make sure what she's writing is very efficient and fast.
  • The tech: The "shift" she describes is almost analogous to multiplying a number by 100. Instead of taking time to multiply each digit the standard way as for any two numbers, you can just add two zeros to the end of the original number. Much faster. [... but I have a techy comment; see below.]

Cameron's wall of code on the wall

  • The gist: It's 3 columns of Cameron's assembly language code for the BIOS. It's not the whole BIOS, and judging from Gordon's awe, it's not copied from IBM's BIOS.

Other Quotes

"pure megahertz, crank up the crystal, attack it with software." -- Gordon
  • The gist: Gordon is brainstorming various ways to make a computer faster.
  • The tech: There's an electronic circuit that uses an oscillating crystal to "tick" millions of times per second (megahertz or MHz). Computers use this ticking "clock" to pace the CPU and other components. Using a faster crystal would increase the speed somewhat, but it is still limited by the maximum clock speed ratings given by the CPU manufacturer. As for the software approach, that is about writing software that does the same task in less time, usually by using fewer instructions and/or more efficient steps.

"... we're all unreasonable people, and progress depends on our changing the world to fit us. Not the other way around." -- Joe to Gordon and Cameron in the parking lot.

  • Just Joe: As was noticed already in the show, Joe is well-read and sometimes uses famous people's quotes. This one is attributed to George Bernard Shaw: "The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man."

Misc. & Technical Notes

The "computer" on Cameron's desk (the one that she takes apart) seems to be just a video display terminal. It's basically a monitor and keyboard that communicates data over a wire with a large, business-class computer in another room of the building.

OK, I have to admit, I've never heard of aligning data on octal [bit] boundaries. Yes multiply-by-8 can be done with 3 bit shifts to the left, there's no question there. I'm just curious if there's a real need to do this, or if it's a meaninglessness or misfire of technobabble.

Cameron's third whiteboard (on the floor, a later scene) contains more detailed info about how the CPU processes instructions, apparently relating to floating point arithmetic operations. It includes latency info that might only be a detail of 486 and later CPUs, though. (The 80486 was released 1989).

The guy sitting in front of Joe when he's being introduced to the team looks kind of like Steve Jobs back then. Perhaps just a popular hairstyle and outfit?

The 'stangs: College football, the Southern Methodist University (SMU) Mustangs, in Dallas.

And finally: good research by the show on the 80s-speak! Lots of references and even words that I haven't heard probably since that decade: 700 club, Doctor J, stagflation.
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