Operability of the controler can be restored, having given command of dumping (reset) on the processor. Such functions are carried out by WatchDog Taimer. In this work this system is not realized. Dumping of the microcontroller can be made short-term dumping of the feeding tension or the Reset button located on the forward panel.
The programmable logic is realized on the MK-51 microprocessor of ATMEL firm – AT89C51 which thanks to the built-in FLASH of memory, possesses possibility of electric reprogramming, so fast modernization of the operating program.
On an entrance there are two capacities: the ceramic condenser for elimination of the short-term peaks of current arising when switchings transistors and electrolytic - for maintenance of entrance tension to constants at its slow fluctuations.
The program was written in assembler language for MK-51 with use of system of debugging of AVSIM5 Further the algorithm of work of the program, listing of the program and hex the file representing the image of ROM intended directly for an insertion in a chip is given.
In this academic year project the task to develop a certain industrial controler for work in conditions of production is set. The task can be carried out on the microprocessor with flexible programmable logic, and also on discrete elements with rigid logic.
I Will corrode the external RSh2N-2-1 socket - an electric connector for printed circuit wiring, an arrangement of pins linear. It is intended for work in electric chains of direct and alternating current with frequencies up to 3 MHz and chains of pulse current.
The transistor M2TKI-50-12 module copes the specialized driver - the driver of transistor modules of this kind - IR2112 of International Rectifier firm. The driver is capable to maintain tension to 600 volts. The scheme of inclusion is given below:
As a rule, such strong and fatal hindrances happen very seldom but if the controler carries out part of operations in the debugged technical process, its such refusal leads to emergence of unplanned idle time in work and heavy economic losses.
At a choice of a microprocessor control system the quantity of discrete elements significantly decreases. That simplifies system, and, therefore, increases its reliability. On the other hand failure of the microprocessor (this unusual occurrence in itself, design errors affect more often) conducts to an exit of all system. At the same time there is a need for the operating program. Each type of the microprocessor possesses a row only to it inherent features: architecture, set of teams, functionality and so on. All this was taken into consideration when writing the program for the designed control system.
For increase in rigidity of the printed-circuit board to mount on the special frame cast with the front panel from an easy aluminum alloy it is SCARLET Thickness of a frame and the panel - 3 mm. The payment to fix to a frame by means of coupling screws M
The design of the block is the aluminum chassis on which the printed-circuit board is fixed. The block chassis at the same time is and sending at installation of the block to the basic (or the device is operated. On the forward panel the button of dumping and indicators are fixed. The payment is connected to the dumping button flexible wires.