here's how i'd do it:
;-----
eot equ 00h
.print_immediate:
. pop dph
. pop dpl
. sjmp get_character
.
.send_character:
. mov sbuf,a
. await_send:
. cpl watch_dog
. jnb ti,await_send
. clr ti
.
.get_character:
. clr a
. movc a, @a+dptr
. inc dptr ;bump pointer or ret addr
. cjne a,#eot,send_character ;jif char
. jmp @a+dptr ;xif else; a=0,dptr=@eot+1
;-----

duh