tài liệu rất hay các bạn ạ. nó thích hợp với những người bết chút hiểu biết về tiếng anh!IntroductionThe system presented in this applicationnote implements a simple digital ther-mometer that includes a built-in LCD andRS-485 communication port. It isdesigned around Atmel’s AT89C2051processor, a DS1620 digital thermome-ter/thermostat from Dallas Semiconduc-tor, a small 8 X 2 LED backlit LCD, andan RS485 line interface. The system,shown in Figure 1, can be used as thebasis for developing custom solutions fornetworked and stand alone data collec-tion and control equipment. It can becentrally powered due to its low currentrequirement and its small size allows it tobe placed almost anywhere.SoftwareThe LCD driver is written entirely in Cand compiles under Micro-C (from Dun-field Development Systems) using thetiny memory model. Although a canoni-cal stack-based implementation, Micro-Cincludes a number of special featuresthat make it quite suitable for generatingROMable code for small sys...