How do you do addition of 32 bit numbers in 8085?

In order to add 32 bit numbers in the 8085, you need to add them 8 bits at a time, tracking the carrys between each add.

LXI B,first_number

LXI H,second_number

LXI D,result

LDAX B ;first byte - no carry in

ADD M

STAX D

INX B; point to next byte

INX D

INX H

LDAX B ;second byte - carry in

ADC M ;note the ADC instead of ADD

STAX D

INX B; point to next byte

INX D

INX H

LDAX B ;third byte - carry in

ADC M

STAX D

INX B; point to next byte

INX D

INX H

LDAX B ;fourth - carry in

ADC M

STAX D