Assembly language program for factorial of number 0,1,2,3,4, 5,6,7 and 8

Program:

lxi h,0000H;

mov D,m;

INR D;

MVI B,1;

MVI C,0;

MVI E,0;

MVI L,1;

LOOP:     MVI A,0;

    LOOP1: ADD L;

        JNC NOCARRY;

        INR C;

       

NOCARRY: DCR B;

   

    JZ NEXT;

    JMP LOOP1;

    NEXT: MOV E,A;

        MOV A,L;

        INR A;

        CMP D;

        JZ END;

        INR L;

        MOV B,E;

        MOV H,C;       

        MVI A,0;

        PRECARRY: ADD L;

        DCR H;

        JNZ PRECARRY;

       

        MOV C,A;

        JMP LOOP;

     

END: MOV A,E;

    STA 0002;

MOV A,C;

STA 0001;

    HLT;

Observation:

6!=>  2001: 02    2002: 208

we know that value of  6!  is 720(i.e. 256+256+208), 8085 use 8bit memory so memory over flow become two times that represent carry 02 and remaining value is 208 

7!=>  2001: 19    2002: 176

we know that value of  7!  is 5040 (i.e.256*19+176), 8085 use 8bit memory so memory over flow become 19 times that represent carry 19 and remaining value is 176

8!=>  2001: 128    2002: 157

we know that value of  8!  is 40320 (i.e.256*157+128), 8085 use 8bit memory so memory over flow become 157 times that represent carry 157 and remaining value is 128

Result:

Input values at 0000 address	Output value at 2002	Carry at 2001
1	1	0
2	2	0
3	6	0
4	24	0
5	120	0
6	208	02
7	176	19
8	128	157
0	1	0