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Team RFID C ritical D esign R eview. Mike Loptien Kirk Spowart Mike Gauthiere Chris Reid Vincent Wu. Preliminary Concept. Read an RFID tag from 10 feet Implement WIFI capabilities GPS integration Use microcontroller. Problems.
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Team RFIDCriticalDesignReview Mike Loptien Kirk Spowart Mike Gauthiere Chris Reid Vincent Wu
Preliminary Concept • Read an RFID tag from 10 feet • Implement WIFI capabilities • GPS integration • Use microcontroller
Problems • Current technology cannot read a passive tag from more than 5 inches • Active tags are generally encrypted and very hard to use • Active tags would require construction of our own antenna and reader hardware • Wifi too difficult for this semester alone • GPS too costly and not necessary for our project
Revised Concept • Read a passive tag from 3-4 inches • Implement a touch screen and high-resolution display • Store data on an SD card • Audio output • NIOS II on Cyclone II FPGA
Applications • Grocery store: embed a passive tag in the price tags of items and store data about that item in the reader • Retail stores: similar idea • Museum: scan a tag near an exhibit to get info about it • Basically a good way to tie information to a physical object
RFID Hardware • ID-12 • Passive tag reader • Max read range: 4” • Simple Circuit and data reading
Collision Detection • Collision detection is handled by the ID-12 • It only outputs data when it correctly reads and decodes a tag
Output • Output on D1, pin 8 • LED Control on LED, pin 10 • Format Select on +/-, pin 7 • 176 bits of output
Output • Output is inverted • 176 bits at 9600 baud • 16 serial packets, 1 start bit, 8 data bit, 2 stop bits and 0 parity bits • Least significant bit first • Transmits ASCII characters
Output Example • Checksum • XOR of all output packets
Processor The Cyclone II
Cyclone II • Up to 50MHz • Will contain the NIOS II, SPI bus, Graphics controller, and RFID translation logic • Cyclone II has good documentation, good supporting software, good expandability
NIOS II • Implemented on the Cyclone II FPGA • Fully customizable processor • Customizable onboard RAM • C compatible through the Altera IDE
NIOS II • Used to control data input and output • Video controller • RFID input analyzer • SD interface • Programmed through USB blaster • SPI bus, UARTs, Ram, Interrupt Priority, Custom Pin selection
SD Breakout Board • COM : Common - Connects to the housing • WP : Write Protect Detect Switch • CD : Card Detect Switch • P9 : Not used in SPI mode (Pin 9 on SD Card) • IRQ : Not used in SPI mode (Pin 8 on SD Card) • DO : Serial Data Out • GND : Ground - Connect this to COM to ground the housing • CLK : Serial Clock • VCC : 3.3V Power • DI : Serial Data In • CS : Chip Select
SD Card System Features • Standard Capacity SD Memory Card: Up to and including 2 GB • High Voltage SD Memory Card – Operating voltage range: 2.7-3.6 V • Default mode: Variable clock rate 0 - 25 MHz, up to 12.5 MB/sec interface speed (using 4 parallel data lines) • Card removal during read operation will never harm the content • Built-in write protection features (permanent and temporary) • Card Detection (Insertion/Removal)
Working With an SD/MMC • Learn to communicate with SD/MMC on Altera Board • Connect our own SD/MMC breakout board and communicate
SD Memory Card Communication Channel • Six-wire communication channel (clock, command, 4 data lines) • Error-protected data transfer • Single or Multiple block oriented data transfer
SD Timing • When reading and writing to the SD card, the key problem is timing. The program must adhere to strict read/write timing to read and write data to/from the SD card. Read Timing Write Timing
SD Card and SPI • Command from host to card is fixed 6 bytes packet • NCR-Command Time Response 0-8 bytes for SD • DI signal must be kept high during read transfer • When a command frame is transmitted to the card, a response to the command will be sent back to the host
Data Transfer • One or more data blocks will be sent/received after command response • Data block is transferred as a data packet that consist of Token, Data Block and CRC • Stop Tran token means the end of multiple block write, it is used in single byte without data block and CRC
Read Data Single Block Read Multiple Block Read
Write Data Single Block Write Multiple Block Write
Touch Screen • Sharp PSP Screen: • 480x272 Resolution • 24 bit color (8 for each R, G, B) • CLK, Hsync, Vsync, DISP Control pins • CLK = 9MHz • Vsync = 17.1 KHz • Hsync = 60 Hz • Hantouch Touch Panel • 4 wire analog resistive • Requires A to D converter to determine location of touch
Graphics Controller Design • Goal: Accept commands from NIOS processor to create image and control output to the LCD screen • Solution: Create a “Soft Graphics Controller” on the Cyclone II FPGA • Command set • Write text • Write vector shapes • Write bitmaps • Manage image ‘layers’
Graphics Controller Design • Rasterizer • Convert characters into bitmaps & write to layer • Convert vector shapes into bitmaps & write to layer • Write bitmaps to layer • Layer Parser • Determine layer order, size & position • Write parsed layers to frame buffer • Screen Control Logic • Manage LCD control pins • Clock dividers, etc. Layer Example
PDA Controller • Texas Instruments TSC2102 PDA Controller Chip • Configuration & communication via SPI • A to D converter for touch panel • A to D converter for battery voltage level measurement • Stereo audio DAC & headphone amp • Multiple audio codecs
Battery Power System • Two ways to design battery power system for RFID reader • Main option is to use a flyback regulator and transformer with three secondary windings • Alternate option is to use three linear voltage regulators
Pros and Cons of Flyback Regulator • Pros: • May use less power, parts may be less expensive, we would gain practical knowledge and experience • Cons: • More time would be required, voltage regulators still needed so flyback regulator and transformer may be superfluous, not a very big part of project so may not be worth several weeks of effort that can be spent on other parts of the project
Pros and Cons of Linear Voltage Regulators • Pros: • Much simpler to implement battery system, can handle the amount of juice we’ll need to power devices • Cons: • May consume more power