Windows 7 license key

[Angrboda]

My first computer system:

The central processor (CPU) and central memory (CM) operated in units of 60-bit words. In CDC lingo, the term "byte" referred to 12-bit entities (which coincided with the word size used by the peripheral processors). Characters were six bits, operation codes were six bits, and central memory addresses were 18 bits. Central processor instructions were either 15 bits or 30 bits. The 18-bit addressing inherent to the Cyber 170 series imposed a limit of 262,144 (256K) words of main memory, which was semiconductor memory in this series. The central processor had no I/O instructions, relying upon the peripheral processor (PP) units to do I/O.

A Cyber 170-series system consisted of one or two CPUs that ran at either 25 or 40 MHz, and was equipped with 10, 14, 17, or 20 peripheral processors (PP), and up to 24 high-performance channels for high-speed I/O. Due to the relatively slow memory reference times of the CPU (in some models, memory reference instructions were slower than floating-point divides), the higher-end CPUs (e.g., Cyber-74, Cyber-76, Cyber-175, and Cyber-176) were equipped with eight or twelve words of high-speed memory used as an instruction cache. Any loop that fit into the cache (which was usually called in-stack) would run without referencing main memory for instruction fetch. The lower-end models did not contain an instruction stack. However since up to four instructions were packed into each 60-bit word, some degree of prefetching was inherent in the design.

As with predecessor systems, the Cyber 170 series had eight 18-bit address registers (A0 through A7), eight 18-bit index registers (B0 through B7), and eight 60-bit operand registers (X0 through X7). Seven of the A registers were tied to their corresponding X register. Setting A1 through A5 read that address and fetched it into the corresponding X1 through X5 register. Likewise, setting register A6 or A7 wrote the corresponding X6 or X7 register to central memory at the address written to the A register. A0 was effectively a scratch register.

I began my computing career in 1977, reading Byte magazine and Scientific American, attending ACM lectures at the university, and sneaking games of text based Star Trek on the university time-sharing mainframe after math classes there using stolen passcodes. The next year, I was a sophomore in high school, using the similar Cyber 170 mainframe hosted at the other university campus 200 miles away to do homework for computer class. (And NOTHING else, I swear!)

Several years down the road, after using the mainframes and the Apple II my high school owned (and teaching myself five different computer languages on them), I purchased a Corona brand IBM-PC clone in 1984. I spent most of my time with that learning programming, writing mostly in C, Turbo Pascal, and 8086 assembler.