Multiplication of 6-byte numbers in 8085 assembly language?

Answer 1

You may be able to find a multipication operator in your assembler instruction set, but for something this basic, I would recommend developping your own specialized version using shift registers and addition - this will be much more efficient in clock cycles as opposed to a canned multiplier.

Answer 2

XRA A

// Set A register to 0

LXI B,0909

// Load 9 into register B and 9 into register C

// These are the numbers to multiply (adjust accordingly)

LOOP: ADD B

// Adds 9 to register A

// If your assembler does not handle variables,

// drop the LOOP: and refer to the line number

// when you want to return to this point

DCR C

// decrease the value in register C by one

JNZ LOOP

// checks for Zero flag, if not found returns to LOOP

// use the two bytes of your line number if you can not use LOOP

HLT

// Halt your program