Intel 8080

                ; memcpy --
                ; Copy a block of memory from one location to another.
                ;
                ; Entry registers
                ;       BC - Number of bytes to copy
                ;       DE - Address of source data block
                ;       HL - Address of target data block
                ;
                ; Return registers
                ;       BC - Zero
 
1000                        org     1000h       ;Origin at 1000h
1000            memcpy      public
1000  78        loop        mov     a,b         ;Test BC,
1001  B1                    ora     c           ;If BC = 0,
1002  C8                    rz                  ;Return
1003  1A                    ldax    d           ;Load A from (DE)
1004  77                    mov     m,a         ;Store A into (HL)
1005  13                    inx     d           ;Increment DE
1006  23                    inx     h           ;Increment HL
1007  0B                    dcx     b           ;Decrement BC
1008  C3 00 10              jmp     loop        ;Repeat the loop
100B                        end