Beautifully explained. I was struggling with learning fetch-decode-execute cycle. Your tutorial has cleared up my confusion. Thanks for the lessons. I will now have to watch this video three or four times just so to commit this to memory. Just subscribed.
I'm entranced by this. I had the pleasure of reading something similar, and I was truly entranced. "The Art of Meaningful Relationships in the 21st Century" by Leo Flint
Very helpful of the order of the cycle however how are the CU and ALU involved? I assume the control unit just controls this whole process and tells the CPU as a whole what to do? And the arithmetic logic unit fetches the instruction from the instruction register and does the instruction(adding)?
So am I correct that: 1)The program is started from an input device and the command travels along the Control Bus to the CU. 2) The Control Unit then contacts the PC along the CPU bus. It moves the counter to MAR (and increments the PC), goes along the address bus to RAM, 'fetches' the contents of the address, transfers the contents back along the data bus and stores it in MDR. That is the Fetch part completed. 3) Then the Control Unit continues to work in Decode. The CU transfers the contents of MDR to IR, which decodes the contents and puts the decoded data into the Accumulator. That is the end of the Decode part. 4)Then the Execute starts. The ALU then performs the arithmetic or logic and sends the output along the data bus to the output device. That is the end of the Execute part.
Sorry I think you might be slightly incorrect. Fetch 1. PC sets MAR to 0 2. (extra) control signal sent along the control bus signifying a read signal 3. address from MAR is sent to the RAM 4. Memory location is read and the data is taken along the data bus and stored in the MDR Decode 5. Data in MDR is transferred to the IR 6. IR is transferred to the decoder in the CPU along the CPU bus to figure out what the instruction means. Execute 7. CPU sends signal along the address bus and stores it in the accumulator If instruction involves a calculation the CPU sends the stored address to perform calculations with the value of the accumulator If the instruction involves storing data the value of the accumulator is transferred into the RAM along the data bus after a control signal is sent along the control bus signifying a write instruction and the address bus is sent signifying the memory location of storage.
Hi Sir. How can we access to the data in memory location 4 without informing the Memory address register. I think that after decoding the 1st instruction, the MAR gets 4 then data is fetched and put in accumulator. Then We look up PC we find 1, which will be copied in MAR to serach for the next instruction.
So the CU (Control Unit) is responsible for sending the signals out which control what is going on in the computer. The signal speed is dictated by the clock, which is also in the control unit. The ALU (arithmetic and logic unit) is responsible for performing calculation on the data (for example is number x bigger than number y and so on).
Thanks for this I have a test tomorrow and my computer science teacher is useless so this helped a lot
Beautifully explained. I was struggling with learning fetch-decode-execute cycle. Your tutorial has cleared up my confusion. Thanks for the lessons.
I will now have to watch this video three or four times just so to commit this to memory.
Just subscribed.
Thanks very much!
Just a masterpiece⭐⭐⭐. Finally unnderstood it because of you. Thank youuuu😊😊😊
Wow, this is the best thing ever! Thank you.
This deserves more likes ❤
I'm entranced by this. I had the pleasure of reading something similar, and I was truly entranced. "The Art of Meaningful Relationships in the 21st Century" by Leo Flint
Well done thanks for the nice explanation.
I watched and read about it many times, but now I finally got it. Thank you :)
Great explanations in an easy and understandable way. Thanks Sir!
brilliant! So well explained! I finally get it all! Thank you! :)
Very helpful of the order of the cycle however how are the CU and ALU involved? I assume the control unit just controls this whole process and tells the CPU as a whole what to do? And the arithmetic logic unit fetches the instruction from the instruction register and does the instruction(adding)?
Great video but CU and ALU weren't mentioned :/
Especially at 1.5 speed!
absolute banger of a little wee film here. keep cracking!
got my CS mock tmr im absolutely finished😭
how'd it go?
@@gokiburi9 got a 5
Very nice
oh my god thank you so much for this!
No problem!!
So am I correct that:
1)The program is started from an input device and the command travels along the Control Bus to the CU.
2) The Control Unit then contacts the PC along the CPU bus. It moves the counter to MAR (and increments the PC), goes along the address bus to RAM, 'fetches' the contents of the address, transfers the contents back along the data bus and stores it in MDR. That is the Fetch part completed.
3) Then the Control Unit continues to work in Decode. The CU transfers the contents of MDR to IR, which decodes the contents and puts the decoded data into the Accumulator. That is the end of the Decode part.
4)Then the Execute starts. The ALU then performs the arithmetic or logic and sends the output along the data bus to the output device. That is the end of the Execute part.
Sorry I think you might be slightly incorrect.
Fetch
1. PC sets MAR to 0
2. (extra) control signal sent along the control bus signifying a read signal
3. address from MAR is sent to the RAM
4. Memory location is read and the data is taken along the data bus and stored in the MDR
Decode
5. Data in MDR is transferred to the IR
6. IR is transferred to the decoder in the CPU along the CPU bus to figure out what the instruction means.
Execute
7.
CPU sends signal along the address bus and stores it in the accumulator
If instruction involves a calculation the CPU sends the stored address to perform calculations with the value of the accumulator
If the instruction involves storing data the value of the accumulator is transferred into the RAM along the data bus after a control signal is sent along the control bus signifying a write instruction and the address bus is sent signifying the memory location of storage.
Hi Sir. How can we access to the data in memory location 4 without informing the Memory address register. I think that after decoding the 1st instruction, the MAR gets 4 then data is fetched and put in accumulator. Then We look up PC we find 1, which will be copied in MAR to serach for the next instruction.
Nicely explained. Could you explain how do CU and ALU take part of this process? What do they do when this process happen?
So the CU (Control Unit) is responsible for sending the signals out which control what is going on in the computer. The signal speed is dictated by the clock, which is also in the control unit. The ALU (arithmetic and logic unit) is responsible for performing calculation on the data (for example is number x bigger than number y and so on).
All jokes aside (And immaturity from my classmates), this was a useful video. Thanks.
No worries - thought they were bot spam!
crystal clear! thanks!
A good sketch to explain but inconsistent in using the memory and Data registers.
Dear teacher, what is purpose of instruction register ? if i see this video,the same is copied to
instruction register from memory data register .
My best guess is that it stores instruction that's fetched after the contents of the address are copied in the in MDR
Thanks for this vid, I learnt how to use K,J,L shortcuts on da u tube #ad
what about adding other numbers , can we still use LOAD 4 and ADD 5..?
Yep - once one cycle is over then the whole the next cycle follows the same pattern with potentially different, or the same numbers.
best video probably.. explanation was to the point
Thanks! That’s how I try to make all my vids - keep to the point.
Thanks nice tute.
Please use mic for explanation for better audio quality
Yes everyone from whitworth
It's not the ALU that does the math???
#hallamforresident