Computer input/output-systems

The importance of the graphic capabilities of computers is rapidly increasing. More and more computer applications in chemistry rely on graphic input/output systems, and the popularity of so-called modelling systems is growing at an astounding rate. 

The design must ensure that records generated by computer systems conform to their specified content. Records covering computer inputs, outputs, and data must be accurate. The computer system should also include built-in checks of the correctness of data that are entered and processed. Manual entry of critical data should be subjected to a confirmation check within the design that may be either manual or automatic. 

Aside from the processor, the most important chip on the motherboard is the basic input/output system (BIOS) chip. This chip is a special memory chip that contains the BIOS software that tells the processor how to interact with the rest of the hardware in the computer. The BIOS chip is easily identified if you have a non-clone computer (e.g. Compaq, IBM, HP, etc.), this chip will have the name of the manufacturer and usually the word BIOS. For example, the BIOS chip for a Compaq will say something like Compaq BIOS on it. For clones, the chip will usually have a sticker or printing on it from the three major BIOS manufacturers (AMI, Phoenix, and Award). 

HOS stands for Basic Input/Output System. The BIOS communicates between the computer and devices. The BIOS is usually stored in ROM. It was created by IBM to act as a translator to run the same operating systems on different hardware platforms. When the operating system needs to access a piece of hardware, it would now ask the BIOS, rather than just taking control of the hardware. The use of BIOS prevented programs from fighting over hardware. As long as the operating system (such as DOS) uses the BIOS for its hardware requests, it can run on different hardware platforms. The BIOS creates a standard reference point for many different types of hardware. 

ROM ROM stands for read-only memory. It is called read-only because it can t be written to. Once the information has been written to the ROM, it can t be changed. ROM is normally used to store the computer s BIOS, because this information normally does not change. The system ROM in the original IBM PC contained the Power-On Self Test (POST), basic input-output system (BIOS), and cassette BASIC. Later IBM computers and compatibles include everything but the cassette BASIC. The system ROM enables the computer to pull itself up by its bootstraps, or boot (start the operating system). 

The next topic you learned about was the Basic Input Output System (BIOS). The BIOS is the software hard-coded into a chip on the motherboard and manages the relationships between the hardware resources of a computer and the operating system. In this section you learned about the different brands of BIOS software and the major differences between them. 

The system BIOS (basic input/output system) is software (usually stored on a ROM chip) that contains all of the code required to control the keyboard, display screen, disk drives, serial ports, and various other PC components. Basically, the BIOS determines what a computer can do without accessing any outside software. 

BIOS (basic input/output system) The ROM-based software on a motherboard that acts as a kind of interpreter between an operating system and a computer s hardware. 

Basic Input-Output System (BIOS) Computer program that allows the central processing unit (CPU) of a computer to communicate with other computer hardware. 

A read-only memory (ROM) chip contains instructions for the basic input-output system (BIOS) that all the peripheral devices use to interact with the CPU. This process is especially important when a user first turns on a computer for the boot process. 

HMI is the human to machine interface in a system. It is the operator interface or UI, which in modern systems is typically a computer screen with computer input-output controls for the operator. HMI is also the application of human factors and human engineering to system design to ensure the safe and reliable operation of the system throughout its life cycle. Since personnel are a major component of any system, special design consideration must be given to human performance. HMI is also sometimes referred to as MMI. HMI is identical to the more recent term HSI. 

A typical transputer architecture. The transputer (sometimes referred to as a computer on a chip) has four input/output links (0, 1, 2, 3) to other transputers, a channel for inputting/requesting data (event link), some built-in random-access memory, an interface to the main operating system (clock, boot, etc.), and an external memory interface. Internal communication is via a bus. 

Any program developed in-house must be easy to use, or user-friendly. If the program has various options for input, analysis, computation, and output, then it must provide the user with a fast way to select them. To meet this need, the system is likely to be menu-driven. The peripheral interactive devices such as mice, joysticks, light pens, graphic tablets, and templates are helpful and often used to expedite the selection process. 

The next task is to seek a model for the observer. We stay with a single-input single-output system, but the concept can be extended to multiple outputs. The estimate should embody the dynamics of the plant (process). Thus one probable model, as shown in Fig. 9.4, is to assume that the state estimator has the same structure as the plant model, as in Eqs. (9-13) and (9-14), or Fig. 9.1. The estimator also has the identical plant matrices A and B. However, one major difference is the addition of the estimation error, y - y, in the computation of the estimated state x. 

Four serial (RS232) ports are provided for flexible communications to other instruments, i.e. autosamplers. In addition, five analogue inputs, tvsro analogue outputs and 3 TTL input/outputs are provided to ensure complete flexibility. These allow auxihary instruments under direct control and the abihty to process data generated by these in real time. These features extend the range of facihties on these expensive but worthwhile analytical techniques. There is no doubt that future developments in computing will continue to have a radical impact on these instrumental systems. 

The TRAACS 800+ is controlled by a personal computer and the features provided include complete interactive control via keyboard or mouse calculation of results as necessary taking into account baseline or sensitivity drift, graphical output of calibration curves for all calibration types—either Hnear or non-hnear, input facility for sample identification data allowing storage on disc and real-time results together with chart traces on a computer printer. The programs allow easy access to input or data files and connection to other computers, and gives system performance verification to CLP standards and built-in QC charts. 

The majority of MAECIS is written in FORTRAN with a few assembler routines for database management. The program is currently running on a VAX 11/780 computer system and uses Tek-ronix 4025 graphics terminals as the primary input/output devices. MAECIS is a command oriented program that has a built in prompt mechanism to assist the user with commands. It also has a HELP section that provides the user with detailed online instructions. 

Field operating personnel have access to the computer through a man-machine input/output (I/O) system located in the Field office. The I/O equipment consists of a cathode ray tube (CRT) with attached keyboard, a card reader and a printer for permanent copy of transmitted information. The I/O system supplies all alarms and operating data needed to monitor production operations. 

MINICOMPUTERS. The next step up is a minicomputer based integrator, which may service up to perhaps two to three dozen chromatographs simultaneously. Examples of this class are the 3352-B system of Hewlett-Packard and the PEP-2 system of Perkin-Elmer. The minicomputer may have multiple input/output devices to service two or more locations independently, and may make the computer available (through a language like BASIC) to do further calculations on chromatographic results or to do general laboratory calculations. 

The order of testing should be considered to ensure retesting is minimized. Operator interface and screen displays are best tested before the system is used for other tests. Input/outputs need to be satisfactorily tested before other tests that are dependent on proven I/O signals, and trend display testing may be needed to support loop testing. For interfaces to other computer systems the main consideration is which system controls the access, selection, transfer, and use of validated data. 

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