So, who noticed the two mistakes on page 18? (2 Viewers)

i4gotmypass

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I also got all outputs 0 on the question with the NOR gate. is there a way to register a complaint with the BOS because that question was stupid as hell and i'm worred they might not notice. I wrote on the paper 'why does the nor gate have only 1 input' and 'why are the 2 output signals tied together' in hopes they see something wrong but i don't know..

part B about the word size I had a table with 4 addresses (2F,30,31,32) each holding a byte / character since a word size of byte means each address holds 8 bits.
 

Brad.1990

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i4gotmypass said:
I also got all outputs 0 on the question with the NOR gate. is there a way to register a complaint with the BOS because that question was stupid as hell and i'm worred they might not notice. I wrote on the paper 'why does the nor gate have only 1 input' and 'why are the 2 output signals tied together' in hopes they see something wrong but i don't know..

part B about the word size I had a table with 4 addresses (2F,30,31,32) each holding a byte / character since a word size of byte means each address holds 8 bits.
I noticed what I done wrong (thinking an OR gate worked when only ONE of the inputs = 1, did it give a 1), so I got one 1 as my output for E. Lol. Damn.

But hopefully with the error, they should be pretty leeway, and probs give everyone the marks for it. Else, they are marking unfairly.

I had no idea what that 2E Address thing was referring to, so I just turned "FISH" into Hex. Worked for me.

And the Railroad diagram question, I am unsure whether they purposely made the nameing error ("Condition Exp" and "Conditional Statement"), as there was a question asking for the legality of that particular statement.

All in all though, there were some poorly writen questions.
 

bmn

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Terlob said:
Did anyone else get 0 as the output for every input for the logic gate?
Using what I've learned from Wikipedia (I do the other option topic but this stuff interests me):

The gate is NOT(NOTA OR (A OR B)) [assuming C and D are separate inputs]
=NOT(NOTA) AND NOT(A OR B) [using De Morgan's laws]
=A AND NOT(A OR B)
=A AND (NOTA AND NOTB) [De Morgan's laws again]
A AND NOTA will always give zero
 

Will-E

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this exam was poorly written in some areas.
for that FISH question i just made a similar table with:
F = 00
I = 01
S = 10
H = 11
i thought about using hex but wouldn't that still take up 32 bits anyway? i mean, each letter doesn't have only 1 bit to store it, so that can't be right.....can it? :S
either way, i hope BOS realises this.
same with that logic gate question
i just put 'undefined' for the output, with a statement saying 'NOR gate has only 1 input'
hopefully i get at least some marks for it
hopefully looking at a band 6 though :D
 

fishbulb

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Will-E said:
this exam was poorly written in some areas.
for that FISH question i just made a similar table with:
F = 00
I = 01
S = 10
H = 11
i thought about using hex but wouldn't that still take up 32 bits anyway? i mean, each letter doesn't have only 1 bit to store it, so that can't be right.....can it? :S
I did the exact same thing. I reckon ill get 1 mark for it since it was a poorly worded question and it was a decent attempt.
 

lolsandwicher

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im actually quite happy no one seems to be getting the FISH one because it was so easy

there was no need to even consider the memory location because that is not what it asked you for. you simply had to break up the 4 8-bit binary sequences into 8 4-bit sequences so you could turn it into hexadecimal i.e an 8bit code

if you understood conversions properly you would have realised this

at least this means im +2 on most people

and to everyone who thinks they will get a mark for making an attempt at it while heading in the absolutely wrong direction (READ: fishbulb + those who wrote down memory locations), you will not because the question was perfectly clear that you had to change the binary code into its hexadecimal equivalent

edit: i didnt even consider the mistake they made on the logic gates either. if you really struggled to understand that it was a mistake and were unable to overcome it, its safe to say that you have bigger problems in life

and the condition/conditional error was purposely put there for your discussion on whether the syntax was correct or not. it was a mistake that allowed you to discuss how the statement was illegal because "condition" had not been previously defined and would result in a syntax error if it were to be programmed as is.

i think it all comes down to people doing pretty poorly in the exams and trying to cling on to minor mistakes made by the BOS as an excuse for doing so bad
 
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Terlob

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lolsandwicher said:
im actually quite happy no one seems to be getting the FISH one because it was so easy

there was no need to even consider the memory location because that is not what it asked you for. you simply had to break up the 4 8-bit binary sequences into 8 4-bit sequences so you could turn it into hexadecimal i.e an 8bit code

if you understood conversions properly you would have realised this

at least this means im +2 on most people

and to everyone who thinks they will get a mark for making an attempt at it while heading in the absolutely wrong direction (READ: fishbulb + those who wrote down memory locations), you will not because the question was perfectly clear that you had to change the binary code into its hexadecimal equivalent

edit: i didnt even consider the mistake they made on the logic gates either. if you really struggled to understand that it was a mistake and were unable to overcome it, its safe to say that you have bigger problems in life

and the condition/conditional error was purposely put there for your discussion on whether the syntax was correct or not. it was a mistake that allowed you to discuss how the statement was illegal because "condition" had not been previously defined and would result in a syntax error if it were to be programmed as is.

i think it all comes down to people doing pretty poorly in the exams and trying to cling on to minor mistakes made by the BOS as an excuse for doing so bad
As one of my friends says, "You fail at life".
 

gingyangel

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Terlob said:
As one of my friends says, "You fail at life".
hahahahahaha
but honestly as a struggle SDD student like me didn't even realise there was mistakes in the exam, maybe i was nervous

so people did get 0 for all the output in their truth table..?
i thought i did something wrong...
 

Terlob

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gingyangel said:
hahahahahaha
but honestly as a struggle SDD student like me didn't even realise there was mistakes in the exam, maybe i was nervous

so people did get 0 for all the output in their truth table..?
i thought i did something wrong...
Yep it seems everyone got 0, so you're all good :)

betonit169 said:
hey thats me !
You're famous now lol
 

Will-E

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lolsandwicher said:
im actually quite happy no one seems to be getting the FISH one because it was so easy

there was no need to even consider the memory location because that is not what it asked you for. you simply had to break up the 4 8-bit binary sequences into 8 4-bit sequences so you could turn it into hexadecimal i.e an 8bit code

if you understood conversions properly you would have realised this

at least this means im +2 on most people

and to everyone who thinks they will get a mark for making an attempt at it while heading in the absolutely wrong direction (READ: fishbulb + those who wrote down memory locations), you will not because the question was perfectly clear that you had to change the binary code into its hexadecimal equivalent

edit: i didnt even consider the mistake they made on the logic gates either. if you really struggled to understand that it was a mistake and were unable to overcome it, its safe to say that you have bigger problems in life

and the condition/conditional error was purposely put there for your discussion on whether the syntax was correct or not. it was a mistake that allowed you to discuss how the statement was illegal because "condition" had not been previously defined and would result in a syntax error if it were to be programmed as is.

i think it all comes down to people doing pretty poorly in the exams and trying to cling on to minor mistakes made by the BOS as an excuse for doing so bad
but how can 4 hexadecimal expressions equal 1 8 bit expression??
am i missing something??
 

Terlob

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Will-E said:
but how can 4 hexadecimal expressions equal 1 8 bit expression??
am i missing something??
An example - I dont know what the exact question was

1) 4 hex expressions: 11010011 - 00011111 - 11010010 - 01001010

2) Combine to 11010011000111111101001001001010

3) Covert in sections to Hex

1010 - A
0100 - 4
0010 - 2
1101 - D
1111 - F
0001 - 1
0011 - 3
1101 - D

4) Answer - D31FD24A - 8 bits

Wish I'd done it in the test :p
 

Will-E

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haha, thanks for the explanation.
i still don't get how D31FD24A can equal 8 bits, though.
i know there's 8 symbols, but you need more than 1 bit to store each symbol, don't you?
lol, maybe i should just stop thinking about it :p
 

le-foot

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okay

you CANNOT place hex into a bit :rolleyes:

Remember: the option talks about hardware - and we all know binary is stored in flip flops, which makes up "memory"

Therefore a BIT is either 1 or 0, not ASCII characters, nor digits. That's why the data type "Int" is 16 bits and can only represent -32768 to 32767. (i.e. -2^15 and 2^15-1)
You cannot store 1 to F as a single BIT.

Thus you have to separate it into four memory locations.
 

Will-E

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le-foot said:
okay

you CANNOT place hex into a bit :rolleyes:

Remember: the option talks about hardware - and we all know binary is stored in flip flops, which makes up "memory"

Therefore a BIT is either 1 or 0, not ASCII characters, nor digits. That's why the data type "Int" is 16 bits and can only represent -32768 to 32767. (i.e. -2^15 and 2^15-1)
You cannot store 1 to F as a single BIT.

Thus you have to separate it into four memory locations.
haha, thanks for the explanation. i've decided to just forget about it for now and wait until they release the marking notes and the exam online. for now i'll just focus on improving my guitar skills :p
 

whitey9999

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le-foot said:
okay

you CANNOT place hex into a bit :rolleyes:

Remember: the option talks about hardware - and we all know binary is stored in flip flops, which makes up "memory"

Therefore a BIT is either 1 or 0, not ASCII characters, nor digits. That's why the data type "Int" is 16 bits and can only represent -32768 to 32767. (i.e. -2^15 and 2^15-1)
You cannot store 1 to F as a single BIT.

Thus you have to separate it into four memory locations.
Good stuff
thank god sumone agrees with me lol

And for the actual mistakes, everyone knew that the one line was actually supposed to be two and just count it as two and stop whinging lol its not going to make a difference. If u want an answer for the two becoming one line then just add them together it makes no difference with an OR gate.

And for the 8-bit Binary code did they actually say it was ASCII because EBCDIC has 8-bits in it and you can use that to represent words.
 

Will-E

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i have the exam, and there is no reference whatsoever to ASCII or EBCDIC in the question. i was also wondering what the point actually is in converting the bits to hex, as it makes no difference to the amount of bits needed to store the information. in other words, i think what most people did was put each letter into a different memory location (i.e. 4 locations), and then converted the binary to hex, which would make no difference. Maybe you could argue that they represent the address locations, but the address really has nothing to do with the information it contains.
 

--Lammy--

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Terlob said:
Did anyone else get 0 as the output for every input for the logic gate?
I did! I went through it and just went O.O Screw it, that's just a stupid circuit.
 

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