Abstract

Introduction

Masters work provides designing and development of the universal, flexible device which will able to give a possibility for a computer supervising different external executive mechanisms and to obtain data from the digital sensors for computer processing their values. In picture 1.1 imaging a possible range of use the device.

Picture 1.1 Possible range of use the device

The concept of the developed device provides, that it will have conclusions for 16 executive mechanisms and the bus for sensors.  User independently connects executive mechanisms and sensors to the device, loads developed  by him or another human, program of functioning of these executive mechanisms together with sensor and, the device, according to the program, carries out the programmed actions, or operatively reacts to commands of the user at manual control. The group of executive mechanisms can serve as one object of control, as a few absolutely diverse. In picture 1.2 imaging the example to use the device

Picture 1.2 Example to use the device

Structure of hardware

 In picture 2.1 imaging the block diagram of the device

Picture 2.1 The block diagram of the device

As it is possible to understand from the scheme, the device is under construction on the basis of AVR microcontroller of Atmel (atmel.com) ATmega16. The scheme have RS-232 interface on the basis of microcircuit MAX232 for communication with personal computer. The microcontroller realizes interface Master I2C on external І2С bus which are connected Slave І2С sensors. For each executive mechanism on an output of the device there are 4 relays JQC-3FF powering 10А 277В, the rotor of each relay is switched on one of two other outputs of the relay depending on a condition of the register control (РК) for this relay, that is for each executive mechanism in the device there have 12 outputs which allow these mechanisms to build the interfaces of communication flexibly are stipulated. Besides the device provides the register of a condition (РС) for each mechanism, РС will keep value of any sensors of a position equipped on the mechanism. All РК connected on bus RK, and all РС on bus PC the choice of the necessary register occurs by the decoder РК and decoder РС.

Structure of the software

In picture 3.1 imaging structure of the software

Picture 3.1 Structure of the software

The software consists from:

-         Programs of user - the user are programming actions of executive mechanisms, or operatively them supervises. During functioning the device user are observing of process execution, and brings corrective amendments in a course of the program

-         The driver - loads the program, are developed by user into system memory, during work of the device executes sample of a following command of memory and transfers its to device. Sends to user information about course of work. Organizes an opportunity of manual control of device.

-         Operational system of the microcontroller - organizes communication with computer, accepts and decode commands from it and executes the influences programmed in command about its periphery . Transfers to computer data from sensors every programmed periods of time.

 Software provides 3 operating modes of system:

1)      Mode close by hard real time. Involved if all actions of the device are programmed, in work takes part handler interruptions of the driver which only does sample of a following command and OS of the device. The mode close to hard real time is reached by a high level priority on which executes actions in ISR procedure of the driver (see article “ Research of the mechanisms work Windows 2000/XP for construction on its base the system of real time ” Taitskogo M.S.)

 2)      Mode of manual control for user. The user independently gives commands to the device. The command passes through the driver which it transfers to  OS of device.

     3)        The hybrid mode. Can arise in case of any mistake at work of the device in a mode close by hard real time if intervention of the user is required. Can be and a regular mode - if the user has programmed some actions, and the some has left for control to itsel

Current condition of work

I made researches in the area of accommodation system of real time in Windows 2000/XP, on this theme is written the article: "Research the mechanisms of work Windows 2000/XP for creation on its base system of real time" by Taitskiy M.S. At this time, is designing and assembly units of hardware, writing the operational system for microcontroller and engineering general principles of work the system.

Source

    1)    Research the mechanisms of work Windows 2000/XP for creation on its base system of real time

   2)    ATmega16 Datasheet     www.atmel.com