三字节加法。被加数置于30H~32H单元

　　　加数置于33H~35H单元

　　　　　　　结果置于40H~42H单元

-8031 internal RAM, 40 h ~ 4 fh unit set initial value A0H ~ AFH respectively, then the content of the 40 h ~ 4 fh unit respectively transmitted to the outside of the piece of RAM 0800 h ~ 0800 fh unit, then slice 0800 h ~ 080 fh unit content transmitted to within 60 h ~ 6 fh unit.