Computer Instructions Video Lecture | Computer Architecture & Organisation (CAO) - Computer Science Engineering (CSE)

this video is about computer
instructions as in the previously you
have already seen the format for the
instructions and because of that format
each computer the basic computer has
three instructional format basically the
instructions can retreat I need and each
have a different which watch a format
that we will be talking in this video
firstly the three type of instructions
can be memory reference register
reference or input/output instruction
let's begin with the memory reference
instruction in this case the format is
asshole
okay every format that is only three
format has 16 bits each in the memories
are few instructions we address part
takes zero to in a bloody v12 with with
a specified for the address part one bit
is a fight for the addressing mode bit
and adore three with are specified for
the operation code that is the opcode
now for this type of instruction I can
have two values 0 or 1 we go boys
directed dressings and one part indirect
addressing I hope you remember what is
like an invalid addressing if you don't
remember you can refer to the previous
we do next simply register reference
instruction in this case it was 12 bits
there give register operation of the gun
is registered after the instruction
therefore an operand from memory is not
required
hence 0 to 11 that is 12 bits does not
specify an address might be resistor
operation to be performed the opcode
part is detected as triple ones and the
last left whole bit is zero so whenever
we encounter with three bits as tuple
one we just have to look at the leftmost
bit because if it is 0 it is the
register reference instruction and if
the value of this bit is 1 then in that
case it will be input upper instructions
so these are the three types of
instructions versus magnetic fields
register activex input/output
construction every type of construction
is 16 16 bit log in this case the 12
bits for and track 3 for opcode and one
for the addressing or big reader
coordinate lol for indirect otherwise be
opcode value can be triple 1 in both the
cases by the leftmost bit tell if it is
registered as an instructional or
input/output instruction if it is 0 it
is because reference register reference
instruction if it is 1 then it is input
output instruction and because both of
these does not require offering from the
memory devil in this case the address
part is expand the register operation to
be performed whenever this part is the
input output instruction that has to be
performed thank you