CSCI 255, ENGR 274, ECE 212 -- 3 October, 2000

Announcements

• Homework 5
• Test -- 5 October, 2000

Little memory to big memory

• To make a 2ⁿ×m memory
  • From 2^p×q memories
• An example with decoders and tri-state buffers
• Resizing the memory
  • Going from j×m 2^k to (j+k)×m
    • 6×64 → 9×512

Another way to do this

• Attiah Hakami's VHDL implementation of a seven segment display
• Wayne Lang's seven segment display

Representation of negative numbers

• Does 0 == -0?
• Do even numbers end with 0's
• Are both n and -n represented?
• Are there special rules for adding positive and negative numbers?

Signed Magnitude

Ones Complement

Twos Complement