lecture25 - CMPT 150 The ALU & Memory Page 1 CMPT 150...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
CMPT 150 The ALU & Memory Page 1 Logic Micro-operations b We want to specify Boolean logic operations on strings of bits stored in registers b E.g. C b A B b Other operations: b logical AND b logical OR b logical XOR b A’ logical complement CMPT 150 The ALU & Memory Page 2 Implementing the Logic Unit b Even though AND, OR, and NOT are complete, we’ll also implement XOR because it is a popular logic function b One bit of logical unit using gates and a mux: S 1 S 0 0 1 2 3 4x1 Mux S 1 S 0 Output 0 0 R = A B 0 1 R = A B 1 0 R = A B 1 1 R = A’ CMPT 150 The ALU & Memory Page 3 Combined Arithmetic/Logic Unit (ALU) b We have now developed two separate combinational circuits that do: b 8 arithmetic micro-operations b b 4 logic micro-operations b b Can use a mux to choose whether we want to do arithmetic or logic S 2 operation 0 1 Arithmetic Logic CMPT 150 The ALU & Memory Page 4 Combined Arithmetic/Logic Unit (ALU) S x1 Arithmetic nit 0 1 2x1 Mux unit Logic unit
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 3

lecture25 - CMPT 150 The ALU & Memory Page 1 CMPT 150...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online