Abstract
- Defines the way how a computer system manages and accesses data storage
Important
Accumulator ISA and Stack ISA use implicit operands.
The implicit operand in Stack-based architecture is “top-of-the-stack” whereas in accumulator-based architecture it is a special register called an accumulator.
Accumulator ISA
load A
: Load value from Main Memory into accumulator which is a special Register!add B
: Add value from Main Memory and value in the accumulator. The sum is stored back to the accumulatorstore C
: Store value in accumulator into Main Memory
Load-Store ISA
- Also known as Register-Register ISA
- The data is decoupled from the Register to Main Memory
Data Loading
Can only load data at Word boundaries.
Memory-Memory ISA
Stack ISA
push A
,push B
: We load values from Main Memory onto the Stackadd
: Remove the top 2 values in the Stack, add them, and load the sum onto top of Stackpop C
: Transfer value at top of Stack to Main Memory