Instruction and Instruction Sequencing (1)
Four Types of Instructions
Data transfers between the memory and the processor registers
Arithmetic and logic operations on data
Program sequencing and control
I/O transfers
Register Transfer Notation
Memory Location: LOC, PLACE, A, VAR2
Processor Register: R0, R5
I/O Subsystem Register: DATAIN, OUTSTATUS
The contents of any location are denoted by placing square
brackets around its name: R2 ← [LOC]
Register Transfer Notation: R4 ← [R2] + [R3]
The righthand side of an RTN expression always denotes a value,
and the left-hand side is the name of a location where the value is to
be placed, overwriting the old contents of that location.
评论0
最新资源