Abstract
SCM refers to a system that integrated CPU, Random Access Memory (RAM), Read-Only Memory (ROM), timer/counter , interrupt controller with its port, paralleled I/O interfaces and other components. All these parts make up a complete mini-computer system. As its feature with small, light, weight, cheap, low power consumption, powerful and fast. SCM is used widely both in the national construction and in the military construction.
The subject is how the watering device works with AT89C51. I will use assembly language to program and the equipment can achieve the following main functions: setting the interval between the last and next time you water, setting the duration of each time you water, controlling the electromagnetic valve. The device consists of five main parts including the circuit of the display of LED, the clock conditioning circuit, the button controlling circuit, the indicator light controlling circuit and the electromagnetic valve controlling circuit. With programming, AT89C51 can do very well in displaying time including seconds minutes and hours. And we could also use the seven button and three indicator lights to adjust the time we want. The device will do it very well automatically as we want.
This article describes the basic principles of SCM AT89C51 including the functions of its each pin. This article also specifies the theory of the LED display and the electromagnetic valve. At the same time, it includes the program we need.