Programmable microprocessor

Today s programmable microprocessor controller operating systems are the result of about a half-century of evolution and provide the available repeatability and reliability required on the plant floor. In the past, achieving these objectives meant choosing a vendor-specific operating system and choosing that vendor s entire control system. This can be a... 

Microprocessor Application Programme. Department of Electrical Engineering, Indian Institute ofTechnology, Delhi, India,... 

The use of computers and microprocessors (also known as programmable electronic systems [PES]) in process control continues to grow. They have brought about many improvements but have also been responsible for some failures. If we can learn from these failures, we may be able to prevent them from happening again. A number of them are therefore described below. Although PES is the most precise descnption of the equipment used, I refer to it as a computer, as this is the term usually used by the nonexpert. 

An EMCS is usually a network of microprocessor-based programmable controllers with varying levels of... 

A dedicated microcomputer is interfaced to the Instron instrument in order to collect the raw data. The microcomputer consists of an 8080A microprocessor, 32K bytes of memory, A/D converter, serial I/O for communication, parallel I/O for digital control and sensing, a real-time programmable clock, and vectored interrupt control. 

The management of an analytical chemistry laboratory involves a number of different but related operations. Analysts will be concerned with the development and routine application of analytical methods under optimum conditions. Instruments have to be set up to operate efficiently, reproducibly and reliably, sometimes over long periods and for a variety of analyses. Results will need to be recorded and presented so that the maximum information may be extracted from them. Repetitive analysis under identical conditions is often required, for instance, in quality assurance programmes. Hence a large number of results will need to be collated and interpreted so that conclusions may be drawn from their overall pattern. The progress of samples through a laboratory needs to be logged and results presented, stored, transmitted and retrieved in an ordered manner. Computers and microprocessors can contribute to these operations in a variety of ways. 

All gas chromatography parameters, including temperature programme rates and hold times, are controlled by the microprocessor and set through the CRT keyboard. Up to five sets of parameters can be stored on the computer disk for instant recall. 

Vith the procedure outlined above, simple programs of programmable calculator (TI 59) and microprocessor (ZoO) for finding M(Vh) and <>o(%) were vrritten. The mean elution volume and total variance of the experimental chromatograms of well characterized polymer samples are first calculated according to... 

Intel, 1991] Intel (1991). i860 Microprocessor Family Programmer Reference Manual. Intel Corporation. 

Since the 1970s, process controls have evolved from pneumatic analog technology to electronic analog technology to microprocessor-based controls. Electronic and pneumatic controllers have now virtually disappeared from process control systems, which are dominated by programmable electronic systems based on microprocessor technology. 

Automation of Prep-HPLC. Reverse phase prep-HPLC separation has proven to be a very reproducible technique. For this reason, the process can be automated. In addition to the standard components of an HPLC system, the following are required for automation an autoinjector capable of large volume injections (2.0 to 5.0 ml), a programmable controller (a microprocessor controller), a fraction collector, and a waste valve (3-way valve) controlled by a solenoid (Fig. A). The microprocessor should allow programming of the solvent flow rate, the sequence for solvent gradient formation, the time of injection, advancement of the fraction collector (to collect specific fractions rather than just uniformly incremented advancement), and control of a waste valve. 

The SynchroMed implantable pump was the first externally programmable implant pump to be introduced in the United States (in 1988). The major components are a miniature peristaltic pump, a drag reservoir (18 ml), a battery, an antenna, a microprocessor and a catheter through which infusate is delivered to a specific site. 

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