A words about signed and unsigned integersThe Heritage/1 ALU makes use of two's complement arithmetic for adding and subtracting 16-bits numbers. However, this does not limit the programmer to the use of signed integers in assembly code, as signed or unsigned is mostly a matter of interpretation.
For instance, using the instruction ADD for adding 0xf000 to 0x0001 will result in 0xf001 which can be interpreted either as positive 61441 or negative or -4095. Moreover, when building more powerful arithmetic by software (such as BCD or Floating Point) the programmer is responsibly for defining data types and to make the correct representation and interpretation of the arithmetic sign.
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Homebuilt CPUs WebRing
JavaScript by Qirien Dhaela
Join the ring?
David Brooks, the designer of the Simplex-III homebrew computer, has founded the Homebuilt CPUs Web Ring. To join, drop David a line, mentioning your page's URL. He will then add it to the list.
You will need to copy this code fragment into your page.
Project start date: May 13 of 2009
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