Data transfer group

Data transfer group: These instruction which are used to transfer a data from one register to another or register to memory or vice versa. E.g. MOV, MVI, LDA etc.


a)    MOV Rd, Rs

-          1 byte instruction

-          It copies data from source register too destination register

-          Rd and Rs may be A,B,C,D,E,H,L

-          E.g. MOV A,B;(A<-B)

b)    MVI R, 8-bit data(move immediate instruction)

-         2 byte instruction

-         Loads the 8-bit of data into the specified register

-         R may be A, B, C, D…….etc.

-         E.g. MVI C,20H;C<-20H

c)     MOV M,R(move to memory from register)

-         Moves the content of the specified register to memory

-         Here the memory is the location specified by the content of HL pair register

-         E.g. MOV M, A;([HL]<-A)

d)    MOV R, M

-          1 byte instruction

-          Moves the content of the specified memory to register

e)    MVI M,8-bit data(move 8-bit data immediate to memory)

-          2 bytes data instruction

-          Loads the 8-bit data on the memory location where address is specified by HL pair register.

-          E.g. MVI H, 32H

MVI L, 00H

MVI M, 20H

f)      LXI Rp, 16-bit data(load register pair immediate)

-         3 bytes instruction

-         Loads the 16-bits data immediately to the pair register

-         Rp may be B,D,H

-         E.g. LXI B, 2000H

-          Here, 1st byte=LXI B(op-code)

2nd byte=20H (upper byte operand)

3rd byte= (lower byte operand)

g)       LDA 16-bits address (load accumulators direct)

-          3 bytes instruction

-          Loads the accumulator with the content of memory location whose address is specified by 16-bit

-          E.g. LDA 5000H;A<-[5000H]

h)    STA 16 bit address(store accumulator content)

-         3 bytes instruction

-         Stores the content f accumulator to the specified memory location

-         E.g. STA 5000H;[5000H]<-A

i)       LDAX Rp (load accumulator indirect)

-          1 byte instruction

-          Loads an accumulator from the memory location indirectly specified by pair register.

-          E.g. MVI B, 20H;B<-20H

MVI C, 40H;C<-40H

LDAX B;A<-[2040H]

j)       STAX Rp (here accumulator content indirectly)

-         1 Byte instruction

-         Stores accumulator content to the memory location indirectly specified by pair register

-         E.g. MVI D, 30H; D<-30H

MVI E, 00H; E<-00H

STAX D;[3000H]<-A

k)     IN 8 bit address

-         1 byte instruction

-         Reads data from the input port specified by the second byte and loads into accumulator

-         E.g. IN 40H; A<-[40H]

l)       OUT 8 bit address

-         2 byte instruction

-         Copies the content of accumulator to the output port specified in the 2nd byte.

-         e.g. OUT 40H,[40H]<-A

m) LHLD 16 bit address(load HL register directly)

-         3 bytes instruction

-         Loads the content of memory location to L register next higher address content into H register

-         E.g. LXI H,9500H; H<-95H,L<-00H

MVI M,3AH;[HL][9500H]<-3A

MVI M,20H;L<-01H

MVI M,20H;[HL][9500H]<-20H

LHLD 9500H;

n)    SHLD 16 bit address(store HL register directly)

-         3 bytes instruction

-         Stores content of L register into specified location and content of H register into next higher memory location.

-         E.g. LXI H, 9500H; H<-95H,L<-00H

SHLD 8000H

o)    XCHG(exchange)

-         1 byte instruction exchange DE pair register with HL pair register.

-         E.g. LXI H, 9500H;

LXI D, 1080H;

XCHG; H<-10H, D<-95H, L<-80H, E<-00H