CPU fetch cycle
Can someone tell me if i understand the CPU fetch and execute cycle correctly? based on the following line of code...
LDAA $100
Its motorolla assembly, means load into registerA the value located at memory location 100h
The following is how i believe the fetch/ecute cycles work,can someone tell me if im correct..(*BTW its an 8bit databus and 16 bit adress bus).
1)the isntruction is loaded into the data bus and into the cpu...
2)then the operand is loaded into the data bus and into the cpu...
--This takes two cycles since the operand is 2bytes
3)Since the cpu actually needs the value at the memory location 100,it puts 100 back into adress bus
4)memory places value from adrress 100 into data bus
5)cpu executes since it has instruction and operand now.
LDAA $100
Its motorolla assembly, means load into registerA the value located at memory location 100h
The following is how i believe the fetch/ecute cycles work,can someone tell me if im correct..(*BTW its an 8bit databus and 16 bit adress bus).
1)the isntruction is loaded into the data bus and into the cpu...
2)then the operand is loaded into the data bus and into the cpu...
--This takes two cycles since the operand is 2bytes
3)Since the cpu actually needs the value at the memory location 100,it puts 100 back into adress bus
4)memory places value from adrress 100 into data bus
5)cpu executes since it has instruction and operand now.
0