Computer Science · Oct / Nov 2016 · Paper 13 · Question 5
2210
As printed in the paper
The question as text
Three switches, A, B and C, each send values of 0 or 1 to a logic circuit. Value X is output from the logic circuit. Switch A Switch B Output X Switch C Logic circuit Output X has a value of 1 depending on the following conditions: Switch A sends value 1 AND Switch B sends value 0 OR Switch B sends value 1 AND Switch C sends value 0
Read automatically from the paper; the printed page above is exact.
Show the answer and mark scheme
5(a)[5]
1 mark per correct section. [5]
5(b)[4]
4 marks for 8 correct values 3 marks for 6 correct values 2 marks for 4 correct values 1 mark for 2 correct values A B C Working space X 0 0 0 0 0 0 1 0 0 1 0 1 0 1 1 0 1 0 0 1 1 0 1 1 1 1 0 1 1 1 1 0 [4]
A B C X
5(c)[1]
Register Z [1]
5(d)(i)[1]
(byte) 5 [1]
5(d)(ii)[1]
(column) 4 [1]
5(d)(iii)[1]
corrected byte is: 1 0 0 1 1 1 1 1 [1]
5(d)(iv)[1]
that gives the value: 1 5 9 (follow through applies) [1]
5(d)(v)[2]
Any two from:
– The byte would be transmitted without having 5 consecutive 1’s – The fault condition would not be recognised [2]
Make a free account to save your answers and see your weak topics and ask the AI why a wrong answer is wrong.