I am new to assembly language programming and I am trying to modify someone elses code and they did not comment it very well, so I cannot understand exactly what it is doing, If anyone can help it would be greatly appreciated. It deals with reading a set of inputs that are brought in on the data bus. I am not sure exactly how it is being processed....all I know is when an input is turned on it will turn on an internal bit, and that internal bit is used in a program to perform some control.

;This is for In41,42,43
mov r3,#3
XPT05: rrc a
push ACC
jnc XPTOFF
XPTON: mov a,#ON
sjmp XPT10
XPTOFF: clr a
XPT10:
movx @DPTR,a
inc DPTR
pop ACC
djnz r3,XPT05

;now just Concentrate in IN48
rrc a
inc DPTR
rrc a
inc DPTR
rrc a
inc DPTR
rrc a
inc DPTR
rrc a
jnc XXOFF
mov a,#ON
sjmp XX10
XXOFF: clr a
XX10: movx @DPTR,a
inc DPTR