OCR A2 Computing F453 Official Thread 22/06/2016 Exam Discussion

Reply 300

username2460773

12

Here's a link to all the grade boundaries for each year. Last year it was 97 raw for a* and 86 for an a.

Reply 301

Hooch Is Crazy

1

Was there a question about systematic addressing in the paper?

Reply 302

Hooch Is Crazy

1

Was there a question about systematic adressing?

Reply 303

Cascadess

14

Original post by Hooch Is Crazy

Was there a question about systematic adressing?

Don't think so! :smile:

Reply 304

Hooch Is Crazy

1

CascThanks07418

Don't think so! :smile:

I thought i skipped a page when someone asked that :h:

Reply 305

jackkt_

is the answer, the use of characters to represent an address of a store location?

Reply 306

username2460773

12

Original post by jackkt_

is the answer, the use of characters to represent an address of a store location?

yes, e.g. ADD COUNT instead of ADD 45

Reply 307

rossscadding

3

Very Easy paper, pretty glad to be honest :smile:

Reply 308

27matthew37

2

Grade Boundaries gonna be high this year. Easy Paper. Most people were done within the first hour. But I don't know, Grade boundaries for Computing are usually low, so may just balance out.

Reply 309

King_Kauko

1

Thank you OCR :smile:

High grade boundaries though...

Reply 310

Rahmada

Original post by jackkt_

is the answer, the use of characters to represent an address of a store location?

It makes it much easier for programmers to understand and remember the addresses of important locations in the memory. They don't need to remember long strings of binary.

Reply 311

Rahmada

Original post by Sallekmo

Can someone tell me what the answer should have been for the 8 marker about CIR and the 6 marker about scope? And can someone draw the stepwise refinement thing too. Thanks

Discuss what the PC, the MDR, the MAR, the CIR do during execution. Mention how the PC works during a jump instruction I.e. increments until it reaches the value being executed. You can probably mention the flag register during decoding and even the accumulator during execution. Potentially even the general register.

The six marker just wanted you to discuss global and local variables. You could mention public or private but that's only really in OOP so it's probably not needed.

(edited 7 years ago)

Reply 312

wardd012

1

Original post by Rahmada

Discuss what the PC, the MDR, the MAR, the CIR do during execution. Mention how the PC works during a jump instruction I.e. increments until it reaches the value being executed. You can probably mention the flag register during decoding and even the accumulator during execution. Potentially even the general register.

The six marker just wanted you to discuss global and local variables. You could mention public or private but that's only really in OOP so it's probably not needed.

I think the 6 mark question stated something like "multiple variables called by procedures", i think they were looking for something similar to "variables are lost from memory once a procedure has finished executing therefore allowing the variable name to be reused in different procedures" (thats what i put anyway), I also talked about how local variables override global variables with the same name

I mentioned the use of global variables briefly but who knows you could be right :/

Reply 313

wardd012

1

Original post by Hooch Is Crazy

Was there a question about systematic adressing?

Saw this on twitter, someone obviously read the question properly

They asked about "symbolic" addressing where a variable is used to represent an address in memory (for 4 marks....i think)

Reply 314

wardd012

1

Original post by Sallekmo

Can someone tell me what the answer should have been for the 8 marker about CIR and the 6 marker about scope? And can someone draw the stepwise refinement thing too. Thanks

Exactly the same layout with one module at the top (calculating wages) and 4 sub modules underneath including the bullet points mentioned in the question, in the space below you had to describe what stepwise refinement was (modules broken down again and again into smaller modules until solvable algorithms are produced) referring to your diagram as examples plus some explanation behind it

Reply 315

Jameswinchester

2

I broke it down into Wages at top into 2 sub topics of Hours and Government. Under Government was Tax and National Insurance, under Hours was Hours worked and Hourly Rate.

Also What was the answer to why use HLL

Reply 316

Alfie90

4

A lot of people are saying that they think there will be high grade boundaries for this years people, but I sort of disagree. I don't think this years paper was any easier then last years and also this year had no "effortless/easy" marks, for example I've seen a question before worth 7 marks just put putting 7 ticks into a table. In my opinion the grade boundaries will be similar last years and if they are higher I doubt they would they would be more then one mark higher.
Here are last years grade boundaries:
Screenshot 2016-06-22 at 1.29.16 PM.png