Exam responses... (1 Viewer)

[Seraph]

hello would anyone have exam responses for the HSC 2001 2002 Question 25 , both software dev view of hardware?

tried this site there are none for these questions , .....

 

[sunny]

If you could post the question, I'm sure people here can try and answer it.

 

[Lazarus]

Responses weren't published for every question - it's quite possible that they don't exist.

Follow Sunny's advice.

 

[Seraph]

alright

On a specially formatted audio compact disk, the audio player initially reads the
CD_Header information. The CD_Header is located at the start of the CD and
describes the properties of the disk. Using the CD_Header information, the audio
player reads the Song_List_Header. The Song_List_Header specifies the properties
for each song on the disk. The maximum number of tracks any CD can
hold is 50. A program can be written to correctly read and play each track from
the CD using the following information:
Special Data Types (Records):

TIME:
Minutes :Integer
Seconds :Integer
CD_Header:
CD_Type :Character
Total_CD_Time :TIME
Number_of_Songs :Integer
Location_of_Data :TIME
Location_of_Song_List_Header :TIME
Song_List_Header:
Location_of_Song :TIME
Length_of_Song :TIME

Commands (Functions):
Seek(TIME) Position the CD player’s laser to the position TIME
Display(TIME) Display the variable TIME
READ(x) Read data from the CD and assign to variable x for all data types

Play Play the CD at the CD player’s current laser position
Pause Maintain CD player’s laser position, stop reading data
Stop Stop CD player and position the laser to start of disk

Using pseudocode, write a generalised function that will read data from the CD
to a variable of type CD_Header, and to an array that holds information about each track

i dont understand how to approach this qusetion , we are talking about data streams etc from Software dev view of hardware , so do we approach this as a normal algorithm? even so i had no idea how to do this..

 

[hornetfig]

normal algorithm, picture the CD as a file -

The CD header stuff is the first thing you would [block] read from the file.
The next thing is a whole list of Song Headers. So you need to read Song Header records from the CD for the number of tracks specified in the CD header.

Then what a Seek function would do would be to, like a random access file, move to a position in time specified

And the Play function would Seek to the start of a specified track (the Location_of_song read from the Song header) and read the data from the CD for the length of the song (the Length_of_song read from the Song header).

Kind of hard to explain, you'd be better to just try it bearing in mind a CD is basically like a typed (random access) file

 

[Seraph]

so basically

im reading the Cd_header in the CD which is in the form of a record already

into a record Cd_header, now this wording makes it seem like all im doing is reading the Cd_header from the file into a variable cd_header, just copyign the data , which seems very odd to me...

and an array holding info on each track (this means a a single variable type) .. but what is the info on each track? the time of each track? , Location , Length? it can only be these things since it can only be one varialbe type..

How come i have to play each track and seek? the question doesnt seem to be asking it

 

[jesterofenglish]

Anyone

hello would anyone have exam responses for the HSC 2001 2002 Question 25 , both software dev view of hardware?

tried this site there are none for these questions , .....

I got both std packages, but 2001 doesn't have Q25. and 2002 doesn't have exemplar response, so I'll just put up band 5/6 answers for you.

....

OK BOS won't let me put it up 'invalid post' apparently. Let me know if you want me to E them to you.

 

[Terra_Niux]

Email it to me please, terioscent@hotmail.com

 

[Seraph]

yep thanks alot mate

ProsperotheLama@hotmail.com

and yea lama is spelled like that lama

and looking at the std package section of this site i could not find any SDD std packages

 

[simonj2]

does someone have an actually pseudocode answer to this from a practise or something which they could post possibly? i'm having trouble understanding the pseudocode syntax of reading from a record/file...

edit: don't worry for me, my question has been answered here