Question

Problem 1: Assume the following value of ACCA (CPU register "A") and memory contents Answer the questions below. Explain all answers. (15 points) ACCA E4 memory Address Data Sc001 03 Sco02 C2 For the instruction ADDA SCO03 Sco03 FE a. Explain and show how this instruction is executed by the 68HC12 (6 points) the Coutents of SCo03 A and storing it back in A b. Show the values in the CCR register bits ADDA affects all bits in the CCR (3 points) 1ULI11O 2 2 22 TLOOIO V c. Assume this is an unsigned operation-determine the answer (in decimal) and state it is valid and why. (3 points) 42 not taliL (arg Ot f d. Assume this is a signed operation - determine the answer (in decimal) and state whether it is valid and why. (3 points) 0001 1011 O00000u Undid snrane Page 1 of 6 30 becanse

please provide correct solutions. please write neat

Answer 1

Gven Ihat: Acc E4 accumulator Condents The Cne Membri Ihe memory Contint are Addre Civeinstroc tion is 03 C2 $Cool Coo 3 ADDA FE 4 Coo3 addshe conlents Precend in the This instruc hiur) (a) (oCation Acc Acc Coo3 E4FE E4 1FE A ccomulator Qesutt - A cc E2 (k) his addition -he ccR Conten AFter pefomimng Cany Al ejative = Over plow = 0 7 2eYo - (c) Consider he operands as un Adition s 228 O OIo o 1E 254 E2

SoThe maximum Value E 8- bil Yegister But occomulator s 256 but he ReSult s GYeateY Ctore Can able -to FF= over Flowy So i eneyators Carry agit Then 256 MSB Lit Signed So the l us Comsidey ihe ope tands and (d) Cigned Representsthe 0 Posi tive Nesative E 4 - T66 FE