Hewlett Packard LaserJet 6L - Sample Essay
1. 44mb Floppy drive 8X CD-Rom drive Standard Keyboard and Mouse As can been seen the system is capable of running perfectly with most applications what is missing are a printer, monitor and software to run on it. 1. 6. 2 Economical Feasibility Since there is a budget of i?? 100 for the system any new hardware and software purchased must total with in that sum. Luckily in this case the system will not need much expensive upgrades, just a monitor, printer and operating system.
Hardware and Justification For the Monitor I have chosen:- 15″ 510A HANSOL SVGA CRT Monitor which costs i??49, I think this is excellent value money for a monitor which will run perfectly on the system. For the Printer I have decided to choose a black and white laser printer because I think it is most suited for this type of problem as it is fast, the toner lasts long and overall are pretty reliable I have chosen:- Hewlett Packard LaserJet 6L which costs i?? 80 It is a good value printer with a speed of 8 pages per minute. Software For the software I have decided just to purchase MS-DOS as if making the project in Turbo Pascal, it will not require any other type of software.
MS-DOS 6. 22 which costs i?? 15 Using MS-DOS has saved in my estimations saved a lot more money then if we purchased Microsoft Windows and MS Access. Total spent on some very nice upgrades i?? 144 which is within the available fund. 1. 7 Justification of Chosen Solution After carefully reviewing all the solutions I have decided to use bespoke software to tackle this problem. The main reason being I am fairly familiar with Borland Turbo Pascal 7. 0 and have sufficient knowledge in that region to deal with this problem.
Another reason for this decision is that I genuinely believe that the final product will be the simplest and fastest solution since other packages will required large libraries and expensive operating systems, while if made in Turbo Pascal will simply require a basic operating system like Dos and much less things have the probability of going wrong. Not only using dos will it be economically better for the system but due to DOS’s simple nature unauthorised access can be made harder then if say you used windows because in windows there are a larger array of tools and feature which can be used.
1. 8 Data source(s) and destinations(s) The data I will need is basically the Items Mr. Robertson has in stock, these can easily be taken from the register he keeps and double checked manually in the shop, Once the necessary data has been collected it will be placed in a Stock Table. 1. 9 Dataflow Diagram (level 1) for new system 1. 10 Entity-Relationship diagram There will be 2 main entities in this system 1. 11 Targets of New System Clearly the Objectives of the New system will have to be :- * Overall performance of the new system must be faster then the previous system.
Must be more efficient and less mistake prune then the previous system. This will be done using validation rules and checks. * Unlike the previous system data redundancy must not occur. Must require less effort to use then the previous system. * The cost of running the system must be less or at least equal to the previous system. New system must be easy for the user to use and require minimal training to use. Must be stable and contain measures to prevent it from crashing or stop functioning in any way that will affect business.
The previous system had a way of delaying customers wishing to purchase items the new system aims to making the service fast, easy and reliable for the customer. Posses the ability to store details about stock that is available. Log every sale that is made. Have the capability to identify items using a code. A method of alerting when certain type of stock is running low and needs reordering. Allow items which have been sold to be returned and re-added to the stock if possible. Produce a receipt after every sale. At the end of every week the sales can be backed up on an external source.
System must be easy to use and have a clean interface. Be hard if not impossible to make changes that will cause the system to not function or cause any type disruption. Have a secure protection system so no one except Mr Robertson can access the system. Be able to run on basic computer hardware. Design 2 Design 2. 1 Structure Diagram 2. 2 System Flow Chart 2. 3 Data Storage and Organisation 2. 3. 1 Definition of data requirements The Data I will be using in this project will come from the Items which are available in stock at the shop. These will be obtained from the register that is kept in the shop.
2. 3. 2 Identification of Storage Media and Format The data will be stored in text files on the hard drive of the computer, the files can be read and modified by Pascal. The Password details will be kept in a file called “Password. dat” and will be accessed and edited by a record type called “FiveChar” this will simply be an ‘type Fivechar = array[1.. 5] of char;’. The stock details will be kept in a file called “Stock. dat” this will be accessed and edited by a record type called “StockDetail” the variables are displayed in the table below:- Stock Table Format Attribute Name Data Type Description ItemCode.
Integer This will be the unique identification code ItemName String Name of Item and description Price Real Cost of Item InStock Integer The Amount Available in Stock MinStock Integer The Minimum Stock level of Item there should be. The sales details will be kept in a file called “Sales. dat” this will be accessed and edited by a record type called “SalesDetail” the variables are displayed in the table below:- Sales Table Format Attribute Name Data Type Description SaleCode Integer This will be the unique identification code Returned Boolean This will specify if the item has been returned or not. Year.
Word Date, will keep the year Month Word Date, will keep the month Day Word Date, will keep the day H Word Time, will keep the hour M Word Time, will keep the Minute(s) S Word Time, will keep the Second Total Real Will keep the total price of the sale Sold array[1.. 18] of Integer This will keep a list of items code of the items that where sold in this sale, it can keep up to 18 items which have been sold For Backup Purposes the systems will have an option where it archives all the data files to floppy disk, from this the system can resume a state at which the last back up was made in case of data lose.
2. 4 Algorithms for data transformation Data will be processed at a number of places in this project, most notably it will be processed in the check out where once all the Items have been entered a total price will be calculated, this will be done simply with a single variable called ‘total’ every time a new item is added price will be added to the total like :- Total := total + price; Another place where data will be processed is to check when items need reordering here a simple comparison will be made with the minimum stock level of data and current stock level like:-
If InStock <= MinStock then reorder else nothing; 2. 5 Identification Validations The main way of validating data and maintaining the integrity of data will be with the variables I will be setting at the start of the program. For example Variable Validations ItemName in the stock table will be a string so it will only accept 20 characters. ItemCode in the stock table will be an integer so entering a character will bring up an error message, same applies to all integer fields. Input Validations
I will also set validations so that the same Item code can not be entered twice, every time you enter an item code the program will search through the entire stock table using a sequential search, to see if it finds the item code, if it does it will give you an error message and you will have to enter a different Item Code. 2. 6 User Interface (design of input and output forms) 2. 6. 1 Password The system will be protected by a simple but effective password, which will protect unauthorised access to the system.
The password will be stored in an external text file, the system will initially read the password from the text file into memory, Then it will prompt the user to enter a password into the input box below:- When entering the password the characters entered will not show, instead asterisks will show in there place. After receiving the password the system will compare the password read from the file and the user entered password and using IF statements will grant access to system if they are the same or will prompt the user to re-enter password if incorrect. Re-entry of password will be allowed 3 times before the program exits.
If the password has been entered 3 times incorrectly the system will freeze and will require a restart, this will be achieved by a simple infinite loop. 2. 6. 2 Menu System The Menu system will have a list of options which when selected will help you navigate thorough different parts of the program which will bring up the different input and output forms used. The different options which will be displayed will be shown on screen, and one of them will be highlighted to select a option the user will uses the up, down keys to scroll between different options and click enter to select the desired option.
Menu select function 2. 6. 4 Main Menu diagram Main Menu The Main Menu is the menu which is bought up when the system starts after password validation from here all parts of the system can be reached. * Check Out – Clicking the check out option will take you to the checkout here Item codes can be entered, total price is calculated and receipt is printed, basically it’s the cashier part for the shop. Stock Table – This will take you to another menu, here all the stock table related options will be shown Sales Table – This will take you to the sales table menu here all the sales related options will be shown.