270Exam1Sp11solutions

# 270Exam1Sp11solutions - CompE 270 Digital Systems Exam 1...

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

CompE 270 Digital Systems Sp11 NAME:__ SOLUTIONS ___ Exam 1 1 1) Add the 8-bit values (show results as 8 bits : binary, hex, and decimal . 10 pts Add hex: convert binary to decimal Carries: 1 1 1 1 FF hex 1 1 1 1 1 1 1 1 binary = __-1_ Signed Dec + 10 hex + 0 0 0 1 0 0 0 0 binary = _+16_ Signed Dec show results in = 0 0 0 0 1 1 1 1 binary = _+15_ Signed Dec hexadecimal: (1) 0F ____ Is the 2’s comp Result valid? Yes _ Signed decimal: ___ +15 ____ Is the unsigned Result valid? No _ Carry Out: C = 1 __ Overflow: _ No (OV=0) _ 2) Multiply 6 10 times 5 10 in unsigned binary: 5 pts 0110 = 6 or 0101 = 5 x0101 x5 x0110 x6 0110 0000 0000 0101 0110__ 0101__ 11110 =30 11110 3) Convert the following numbers: (5 pts ea) a) 4 bit 2’s comp: 11.01 2 b) Signed hex C0 to decimal: __ -0.75 __ to decimal: __ 192 __ -2+1+0.25 = -0.75 12*16+0 = 192 c) Decimal -1.75 d) Decimal 127 to 4 bit 2’s comp binary: _ 10.01 __ to unsigned hex: _ 7F __ -2+0.25 = 10.01 2^7-1 = 10000000-1 = 0111 1111 2 4) Calculate the following using 4-bit BCD sum, and decimal equivalents: 1 1 1 1 1 10 pts 0 1 0 1 0 1 1 0 BCD = __ 5 6 __ Decimal +0 0 1 0 0 1 0 1

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

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 02/26/2012 for the course COMPE 270 taught by Professor Harris during the Spring '08 term at San Diego State.

### Page1 / 4

270Exam1Sp11solutions - CompE 270 Digital Systems Exam 1...

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

View Full Document
Ask a homework question - tutors are online