Subtraction of two 8 bit numbers

Constraint: The numbers should be such that the result is limited to 8 bits.
INPUT: (2000H) 10h , (2010H) 15h
OUTPUT: (2020H) 05h

Code:

LDA 2000H ; 
MOV B,A
LDA 2010H
SUB B
STA 2020H
HLT