System development And Life Cycle-Implementation and Post Implementation & Maintenance

Implementation

Stage: User training, File / System conversion

Key Question: What is actual operation? Are user manuals ready? Are there delays in loading files?

Results: Training programs, user friendly documentation

• It is concerned with user training, site preparation and file conversion.

• When system is linked to terminal or remote sites it also includes telecommunication network and network testing along with system.

• During final testing user acceptance is tested followed by user training,

• System testing checks the readiness and accuracy of system to access, update and retrieve data from new files.

• If testing is successful program is run with live data or else a diagnostic procedure is use to locate and correct errors.

Post-Implementation and Maintenance

Stage: Evaluation, maintenance and enhancements.

Key Questions: is system running? Should system be modified?

Results: User requirements need, satisfied user.

• There is an aging process require periodic maintenance of hardware and software.

• If new information is inconsistent with design specification, then changes have to be made.

• Importance of maintenance is to continue to bring the new system to standards.

• User priorities, changes in organizational requirements or environmental factors call for system enhancement. It requires evaluation, program modifications and further testing.

• In post implementation it is observed how effectively system is working, what type of actions should taken to maximize the benefits of system.

Some times user requirements are not clearly defined or understood.Some times it happens that recognition of problem is something else, the design by analyst is different, produced by programmer is different and lastly when it is installed to user's site then it is different. None of these matches with user's requirement.

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8085 Microprocessor: De-multiplexing of AD0-AD7 Address and Data Lines

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Interrupts in 8085 Microprocessor: Vectored-Non Vectored Interrupts And Maskable-Non Maskable Interrupts

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What is Interrupt and how it is generated? Interrupt is a signal send by an external device to the processor, to the processor to perform a particular task or work. In the microprocessor based system the interrupts are used for data transfer between the peripheral and the microprocessor. When a peripheral is ready for data transfer, it interrupts the processor by sending an appropriate signal to the interrupt pin of the processor. If the processor accepts the interrupt then the processor suspends its current activity and executes an interrupt service subroutine to complete the data transfer between the peripheral and processor. After executing the interrupt service routine the processor resumes its current activity. This type of data transfer scheme is called interrupt driven data transfer scheme. Types Of Interrupt: The interrupts are classified into software interrupts and hardware interrupts. • The software interrupts are program instructions. While running a program, if a software

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