Source or destination of data outside system Basic







Source or destination of data outside system Basic DFD Symbols External Entity or process within which incoming data flows are transformed into outgoing data flows. Data Flow Place where data are stored File Pathway for data Data Flow System of Interest Data Flow 7

Data Flow Diagrams Customer (A) Customer payment (B) Remittance data Process (D) payment (C) Deposit (E) Bank (J) 8

Data Flow Diagrams Accounts receivable (H) (G) Remittance data (D) Update receivables (F) Receivables information (I) Credit manager (K) 9




Data Flow Diagrams Departments Human resources Time cards Payroll processing system Employee data 13

Data Flow Diagrams Tax reports and payments Payroll processing system Employee paychecks Payroll check Payroll report Government agencies Employees Bank Management 14

CONTEXT DIAGRAM Customer Payment Cash Receipts Process Deposit Bank 15

Physical DFD Customer Cash 1. 0 Sales External Entity Cash and Register Tape Clerk 2. 0 Form 66 W Internal entities File or data store 3. 0 Bookkeeping Verified register tape Cashier Deposit slip and cash Bank BLUE SALES BOOK 16

Logical level 0 Customer Payment 1. 0 Receive Payment DFD Receipts & Receipts Summary Sales Record 2. 0 Compare cash & tape 4. 0 Record Sales Journal Verified receipts summary Validated receipts 3. 0 Prepare deposit Deposit Bank 17













Flowchart Symbols Input/output symbols Symbol Name Document On-line keying Display Input/output; Journal/ledger 30

Flowchart Symbols Processing symbols Symbol Name Manual operations Computer processing Auxiliary operation 31

Flowchart Symbols Storage symbols Symbol Name Magnetic disk Magnetic tape 32

Flowchart Symbols Flow and miscellaneous symbols Document or processing flow On-page connector Off-page connector Terminal Decision 33









MAILROOM Customer RAs ACCOUNTS RECEIVABLE COMPUTER Annotated RAs CASHIER A Key BT, customer, Inv. #, amt. & Ck. # BT Verify, post to A/R Master, log transactions Cash Receipts Endorsed Checks Verify/ Accept Endorse Checks BT Write amt & Ck # on RA Prepare batch totals for RAs AR Master Print end of day reports Annotated RAs Compare Print deposit slip At end of day Endorsed Checks CR Listing Periodically Filed until deposit slip received Compare Summary of Cust. a/c paid CR Total Temp file Deposit slip 1 Endorsed Checks Summary of Cust. a/c paid GL Dept Key: RA = Remittance Advice BT = Batch Total CR = Cash Receipts Deposit slip 2 Deposit slip 1 Bank A 42

CUSTOMER Start MAILROOM Endorse Checks BT Checks RAs ACCOUNTS RECEIVABLE Endorsed Checks Annotated RAs Write amt. & check # on RA Endorsed Checks Annotated RAs Temp file Alternative presentation for mailroom Endorsed checks Annotated RAs Batch total for RAs BT Endorsed checks Annotated RAs A 43

ACCOUNTS RECEIVABLE COMPUTER BT Annotated RAs Verify RA input Key BT, Cust. inv #, amt. & ck. # Input & errors A/R master Alternative presentation for A/R activities Resolve errors Key corrections/ accept input Post to AR Master Accepted input Log transaction BT Annotated RAs Temp file Cash receipts file Until end of day 44


What Are Computer System Flowcharts? Input Storag e Process Output 46

What Are Program Flowcharts? Input data If a condition is met No Yes Perform calculation Update record 47

Flowchart for Processing Credit Orders Enter Start sales order Approved for credit? No Reject order No Backorder Yes Inventory available? Yes Fill order Stop 48



What Are Decision Tables? Stub Condition (Specific conditions) Action (Specific actions) Entry Condition Rule 1 2 3 4 1 2 5 Action Rule 3 4 5 51

Decision Table for Processing Credit Orders Credit approved Order Inventory Order 500 units Reject order Back-order Fill order Give 20% discount a N ? ? X b c d Y Y Y N Y Y ? N Y X X 52





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