1. Virtual Wallet Gates Winkler Yin Shen Jordan Fei Project Manager: Prajna Shetty 18-525 12/02/2009 A handheld device that saves time and money through smart budget management and simplifies shopping experience

2. Outline Product Proposal Market Appeal System Description Schematics Simulation Results Layout Evolution Retrospection Slide 2 Virtual WalletDecember 2, 2009

3. Handheld system that customers pick up upon entering store. Virtual Wallet retrieves information stored on customer’s SecurOne card. Allows user to set a budget and monitor his/her shopping Notifies user if they go over budget. Accesses database and applies existing membership discounts Allows online bill payment and self-checkout Virtual Wallet has functionality to remove items and increase budget if user goes over. Product Description Slide 3 Virtual Wallet Item 1 Item 2 checkout December 2, 2009

4. Design Objectives Minimize cost by optimizing area. Utilize extremely regular layout Robust verification at all design levels Behavioral Verilog Structural Verilog Schematics Slide 4 Virtual WalletDecember 2, 2009

5. Connection to SecurOne SecurOne system is an identification card and reader system. Card contains access to user’s personal information, such as bank accounts. Other 18-525 group designed secure reader system. Reader will be a component of the Virtual Wallet so that the device can get personal information of the user for checkout. Slide 5 Virtual WalletDecember 2, 2009

6. The SecurOne card will be used in every shopping center. This device can be implemented in any store, as it connects to a store’s unique database. Saves shopping time and eliminates checkout lines. Market Appeal Slide 6 Virtual WalletDecember 2, 2009

7. System Description Slide 7 Virtual WalletDecember 2, 2009

8. System Specification Slide 8 Virtual Wallet 30-bit Integer arithmetic units cumulatively calculates amount spent Budget and price calculations are done in cents, with the display placing an appropriate decimal. The RFID obtained by Virtual Wallet is fed to the online database to obtain information about a product and its price December 2, 2009

9. Flow Diagram Scan card and confirm identity Select bank account and input budget Begin shopping Price of items bought is added to total If total goes over budget Remove items to go back under budget Increase budget if possible Slide 9 Virtual Wallet Apply coupons if possible December 2, 2009

10. Functional Design SRAM: Memory to store 32 8-bit item RFID tag. Other information looked up from Online store database. Second SRAM stores budget. Adder: Adding block. 30-bit addition Subtractor: Subtracting block. Will handle discounts and item removals. As items are removed the SRAM remembers the items removed so they will not be added into total costs Registers: Budget and Total registers store values Comparator: Takes in the budget entered by the user and total after each item is scanned checks to see if one is over the budget Touchscreen: User Input (not implemented) Display: (not implemented) Interface to Online Database: Data lines Slide 10 Virtual WalletDecember 2, 2009

11. Functional Design Item SRAM AdderSubtractorComparator Budget FSM USER ID Discount FSM RFID keypad SecurOne card Display SecurOne Database SecureOne Store Database Budget register Input FSM Checks RFID tag against store database to get price etc. Make notes in subtractor Interfacing logic for Database and Display Battery FSM battery total register Slide 11 Virtual WalletDecember 2, 2009

12. Input FSM Initial Connect to SecureOne Select Account Start Shopping Don’t input budget Set budget to max in account Check account Input Budget Not enough in account Display error Enough in account Budget stored in memory Slide 12 Virtual WalletDecember 2, 2009

13. Budget FSM Initial Over Remove item Go over Remove item Check SRAM Make note in subtractor Total not over budget Don’t go over Added another item Make note in subtractor Total still over budget Checkout Check SecureOne Database. Pay Slide 13 Virtual Wallet December 2, 2009

14. Discount FSM Initial Check Database Check SRAM Get nothing Scanned item discount Make note in subtractor No discount Slide 14 Virtual WalletDecember 2, 2009

15. Battery FSM Good Battery Low Battery Battery Good Battery Low Battery Charging When Plugged in Battery Starts Charging and returns to the correct State when unplugged Slide 15 Virtual WalletDecember 2, 2009

16. Virtual Wallet Top Module Slide 16 Virtual Wallet SRAM Control logic FSMs Arithmetic and control logic Binary to BCD converter and controlling logic BCD to Binary converter and controlling logic December 2, 2009

17. Verification Slide 17 Virtual WalletDecember 2, 2009

18. Verification Process Designed blocks in Behavioral Verilog to test design. After individual blocks simulated, top level control logic made to test all pieces together. From Verilog design, built schematics for individual blocks. Tested individual blocks to determine functionality. After each block was confirmed worked, top level schematic tied pieces together with control logic. Tested with multiple vectors to determine functionality. 1 ns clock Tested different functions, such as input budget, remove item, writing to SRAM, etc. Slide 18 Virtual WalletDecember 2, 2009

19. Budget Slide 19 Virtual Wallet Budget of $50 is input, converted to binary (110010), and stored in budget register shifted ten bits higher December 2, 2009

20. SRAM Slide 20 Virtual Wallet Wrote 5 values into SRAM Values of bit and bit_bar are shown here as data is written. December 2, 2009

21. SRAM Slide 21 Virtual WalletDecember 2, 2009

22. SRAM Slide 22 Virtual WalletDecember 2, 2009

23. Arithmetic Slide 23 Virtual Wallet Total goes over budget, over signal goes high Remove item to send total back under budget Addition: price of new items added to total December 2, 2009

24. Layout Evolution Slide 24 Virtual WalletDecember 2, 2009

25. Initial Floorplan Slide 25 Virtual WalletDecember 2, 2009

26. Improved Floorplan Slide 26 Virtual WalletDecember 2, 2009

27. Final Layout SRAM Arithmetic: adder subtractor total register Comparator FSMs control logic Binary/BCD converters Slide 27 Virtual WalletDecember 2, 2009

28. Final Layout Top Half Slide 28 Virtual WalletDecember 2, 2009

29. Final Layout Bottom Half Slide 29 Virtual WalletDecember 2, 2009

30. Design Specifications Area ~ 56980μm 2 370μm X 154μm Aspect Ratio: 1:2.4 Transistor count: 18532 Density: 0.32527 transistors/ μm 2 Slide 30 Virtual WalletDecember 2, 2009

31. Retrospection Overall the project was completed without too much difficulty or variance from the original plan. The floorplan design changed significantly from the original version to the final layout. Had to account for 30-bit routing Some parts were deemed unnecessary Issues with modelSIM made caused full structural verilog tests impossible Logic which looped onto itself had to be replaced with behavioral verilog. Some library naming issues came up due to having to share pieces between the three of us. Slide 31 Virtual WalletDecember 2, 2009

32. In Conclusion Virtual Wallet provides a safe and secure way to increase shopping efficiency. User is able to check out with Virtual Wallet when done shopping Can be implemented in any store from large chains to mom and pop businesses. Slide 32 Virtual WalletDecember 2, 2009

33. Thank you Questions/Comments? Slide 33 Virtual WalletDecember 2, 2009