Functional Description

8-bit Fixed-point Accumulator-based ALU: SNOWBALL is a fixed point ALU capable of calculating Arithmetic and Logical Functions and No OPs.

The Arithmetic functions are as follows:

  • 2's complement addition
  • Fixed point positive number square root    (Note: taking the square root of a negative number returns an imaginary, which SNOWBALL doesn't allow.)

    The Logical Functions are:

  • AND (bitwise)
  • OR (bitwise)
  • NOT (bitwise)

    The pin usage is as follows:

  • 8 pins for data input
  • 8 pins for data output
  • 3 pins for the OP code input
  • 1 pin for the PLA reset
  • 4 pins for outputting the PLA State Bits.
  • 24 pins total used.

    SNOWBALL uses approximately 2000 x 2800 lambda of the chip.

    Last modified: Sat Dec 12 23:45:25 CST 1998