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ECE 477 Design Review Team 13 Spring 2008 Paste a photo of team members here, annotated with names of team members. Srichand Varun Madhu Anvesh Outline • • • • • • • • • • Project overview Project-specific success criteria Block diagram Component selection rationale Packaging design Schematic and theory of operation PCB layout Software design/development status Project completion timeline Questions / discussion Project Overview • An ordering system will be created where the user will be able to order and pay for the food from the comfort of the table • Consists of a touch screen monitor which displays the restaurant menu and allows the user to select the items • The order is sent through a wireless interface which is received by the receiver • The bill can be paid at the table using a RFID gift card after it is validated Project-Specific Success Criteria • An ability to display information (menus, items ordered, etc.) on an LCD. • An ability to enter choices and select functions via touch screen entry. • An ability to read an RFID card and use decoded user ID to look up personal account information. • An ability to transmit menu choices over a wireless interface (e.g., 802.15.4) • An ability to customize the menu by getting data from database. Block Diagram 12 VDC Supply LCD Screen (NEC 8.4”) Touch Screen Panel 4 2 Graphics Controller (Reach Technologies 42-0105-01) Voltage Regulator and DC-DC Converters (5V to 3.3V) 2 SCI 2 GPIO Microcontroller (Freescale MC9S12C128) 1 SCI RFID Reader (Spark Fun ID – 12) 2 SCI 3 GPIO ZigBee Transceiver (Maxstream XBee Pro) Component Selection Rationale Wireless Transceiver • Chosen component : Max stream XBee Pro - 1 SCI interface Medium Range (300m Indoor) Low power dissipation Built in Antenna • Competing Alternative : Atmel ATmega64RZAPV Component Selection Rationale RFID Reader • Chosen component : Spark Fun ID-12 RFID Reader - 1 SCI Interface Short Range (12 cm) Low Cost Built in Antenna • Competing Alternative : Texas Instruments RI-STUMRD1 Component Selection Rationale LCD and Touch Screen • Chosen component : Reach Technologies 42-0105-01 LCD Touch Screen Kit - Medium size (8.4” diagonally) - External SD memory - SCI Interface • Competing Alternative : Apollo Display Technologies T-51638D084J-FW-A-AB-V399B Touch screen LCD Component Selection Rationale Microcontroller • Chosen component : MC9S12E128 - 3 SCI Ports 80 pin packaging 25 MHz clock Previously known microcontroller family and development environment • Competing Alternative : PIC dsPIC33FJ128MC706 Packaging Design • Constraints - Size and Durability Portability Heat Dissipation Cost Packaging Design • Dimensions - 226mm x 157mm x 47mm • Material - Non conducting material • Screen Size - 8.4 inch diagonally Packaging Design Packaging Design Chosen Enclosure : PACTEC PT-10 External Dimensions: 7.9 x 11 x 3 in Schematic (Microcontroller) Schematic (Clock Generator) • Colpitts Oscillator setting • Manufacturer’s specifications for capacitor and resistor values • 8 MHz Crystal Schematic (ZigBee Wireless) • DIN and DOUT are connected to the SCI • RTS, CTS, Sleep and Reset are connected to the GPIOs Schematic (Power Circuit) • Non-synchronous step down voltage regulator • For both 3.3 V and 5 V • Very high efficiency (up to 87%) Schematic (Headers) • Headers for RFID and Graphic Controller • Pull-up resistors for RTS and TX of Graphic Controller • By-pass capacitor for the RFID header PCB Layout • • • • • • Maximum Dimensions: 7.4 x 10.5 x 3 in 0807 SMD resistors and capacitors 2 Power supplies: 3.3 V and 5 V Maximum Current Draw: 300 mA Nets routed by priority Status: All components placed 90 % routed PCB Layout Top Layer • • • • 12 V – 60 mils 5 V – 60 mils 3.3 V – 30 mils Others – 12 mils PCB Layout Bottom Layer • GND – 60 mils • Others – 12 mils PCB Layout Microcontroller PCB Layout Wireless Transceiver PCB Layout Power Supply Top • All power supply kept together • 12 V input header placed between the two circuits PCB Layout Power Supply Bottom • GND header placed between the two circuits PCB Layout Oscillator Circuit Top • Colpitts Oscillator circuit • 8 MHz crystal oscillator PCB Layout Oscillator Circuit Bottom PCB Layout RFID Header • RX SCI pin • 5 V and GND • RESET tied to +5 V PCB Layout Graphic Controller Header • GPIOs for RTS, Reset and GND using 10k pull up • TX using 10k pull up • GND Software Design • • • • Software is written in C using code warrior Timer interrupt used to create system clock All operations are contained in main loop RFID and Touch screen works on interrupt mode Software Design • Sequence of Operation - Sleep mode Interrupt on touch screen/RFID Display Menu Send order Confirmation Pay Bill Sleep mode Software Design • Completed Interfaces : - Tested RFID interface with 9S12C32 - System Clock • Tasks to complete next : - XBee Interface - Graphical Interface - Software code for customizing and Displaying menu Project Completion Timeline Week Finalize PCB Populate PCB Interfacing Software Design Packaging Testing Documentation 2/243/1 3/23/8 3/93/15 3/163/22 3/233/29 3/304/5 4/64/12 4/134/19 4/204/26 4/275/3 Questions / Discussion