Upload
ataret
View
63
Download
1
Tags:
Embed Size (px)
DESCRIPTION
Aztec PC Oscilloscope. Michael Mason Jed Brown Josh Price Andrew Youngs. Changes in Design since PRD. Spartan 3 Starter kit replaces Spartan 3E Kit Reason: Cheaper and more readily available. Better alternative for low-income students. Not hard to tweak code for the 3E. Siemens 8051 - PowerPoint PPT Presentation
Citation preview
Aztec PC Oscilloscope
Michael MasonJed BrownJosh PriceAndrew Youngs
Changes in Design since PRD
Spartan 3 Starter kit replaces Spartan 3E Kit Reason: Cheaper and more readily
available. Better alternative for low-income students. Not hard to tweak code for the 3E.
Siemens 8051 Reason: Already known by us, provides
enough.PC Communication Serial and USB Initially PC->Scope communication will be
via serial cable to the uC. Scope Data -> PC will de via serial/USB
interface from the FPGA.
Scope
S C
A/DSpartan-3
SDRAM
M C
USBControlle
r
eeprom
Serial
PC
Block Diagram
USB ControllerUM232R UART Interface supports 7/8 bit data, 1/2 stop bits, and Odd/Even/Mark/Space/No Parity Transfer Data Rate 300k to 1Mega Baud (RS232) FIFO receive and transmit buffers for high data throughput.Integrated 3.3V level converter for USB I/O.
Spartan-3 FPGA Board
Xilinx Devices: Spartan-3 (XC3S200)
Clocks: 50 MHz crystal clock oscillator Memory 256Kx16 ISSI - 10 ns SRAM devices
Spartan-3 Starter KitConnectors and Interfaces Xilinx Spartan-3 FPGA w/ twelve 18-bit
multipliers, 216Kbits of block RAM, and up to 500MHz internal clock speeds
-200, -400, and -1000 versions available On-board 2Mbit Platform Flash (XCF02S) 8 slide switches, 4 pushbuttons, 9 LEDs, and
4-digit seven-segment display Serial port, VGA port, and PS/2
mouse/keyboard port Three 40-pin expansion connectors Three high-current voltage regulators (3.3V,
2.5V, and 1.2V) 1Mbyte on-board 10ns SRAM (256Kb x 32)
Spartan-3 Schematic
Expansion Slot Schematic
MicrocontrollerSiemens 805116-bit addressable, 8-bit data, 64kB accessible external RAMBasic control unit for enables, external peripherals (SPI with ADC) Will interface with the computer for sending data and receiving user commands (RS-232).
Microcontroller
Voltage Regulator
Latch, Decoder, EPROM, and SRAM from uC(32kx8 EPROM for program memory) (32kx8 SRAM for external memory)
EEPROM from uC(16kbit serial)
Serial Port
Serial Peripheral Interfacing (SPI)
•SCK (Serial Data Clock): Data is shifted/latched on the rising or falling edge of SCK (see next section). •MOSI (Master Output/Slave Input): Data is transmitted out of this pin if the chip is a Master and into this pin if the chip is a Slave. •CS (Chip Select, active low): Tells the peripheral that a transfer is about to begin.
Analog to Digital Conversion
Differential Input
ADC: 3V peak to peak maximum input
Voltage Reference
Input Stage
Capacitive Impedance matching
1:1, 10:1 Attenuation
AC Coupling
Single-Ended to Differential Stage
Feedback Control
4 Gain Levels: 2, 4, 6, 10
Gain Stage #2
CLC5526: Digitally Controlled Variable Gain Amplifier+30 dB to –12dB
ADS807
Internal Reference Voltage
Input: 3Vpp (V+ - V- <3V)
Clock Input from FPGA:10k to 53M
samples/sec
12-bit Output Buffered, sent to FPGA
Software – FPGA
Labview Module using VESA interface.Communication via virtual COM port drivers. Cause the USB device to appear as an
addition com port available to the PC. Applications can access the USB device
in the same way as it would access a standard COM port.
Software – User GUI
Initial development in both MATLAB and Labview Labview has better interface modules
but more difficult to program the GUI. MATLAB is easier to program the GUI but
the advanced controls will be more difficult
Use Labview to develop GUI with MATLAB as a fallback.
Graphical User Interface
Inputs Data will be inputted via USB from the
FPGA board. Data Format
8 bit data transfer 1 stop bit 0 parity bits
Data speeds will be 300k – 1M baud
Graphical User Interface - cont.
Outputs Serial output to Microcontroller
Data will be 8 bit with 1 stop bit. (RS232) Graphical Output to Monitor
Data Graphs Controls to manipulate data graph and
perform analysis. Control inputs to be sent to micro
controller.
Parts ListPart Quantity Part QuantityTrimCap 1 Perf Board 147 pF Capacitor 2 Power Supply 1300 Ohm Resistor 1 MAX233 (233) 11M Ohm Resistor 1 LM7805 - Voltage Reulator 125 Ohm Resistor 4 MX7821 - ADC 2196 Ohm Resistor 8 Seimens C501 Microcontroller 2392 Ohm Resistor 5 LS7408 - AND Gate 2600 Ohm Resistor 4 74LS156 - Decoder 11k Resistor 4 74LS373 - Latch 1100 Ohm Resistor 12 77C256 - EPROM 1ADS807E 1 62256 - SRAM 1MAX4545 Quad Switches 4 Crystal Oscillator 1THS4215 Opamp 4 Misc Microcontroller PartsCLC5526 Variable Gain Amplifier 1SN54HC541 Tri State Buffer 2UM232R - USB - Serial UART 1EVAL232R - a USB - RS232 converter 1ADS826E - ADC 3SN74HC541NSRG4 - ADC 3THS1040IPW - ADC 3PCB-SSOP-20 : SSOP to DIP Adapter 20-Pin 4PCB-SOIC-20 : SOIC to DIP Adapter 20-Pin 5
Updated Schedule
Timeline – Milestone 1Micro controller
Programming Complete Serial Interface Working
A/D Converter Circuit design complete Prototype complete and tested
FPGA Programming mostly complete USB interface started
Software GUI preliminary programming, simple I/O
PCB Schematics completed for 1st revision.
Timeline – Milestone 2
FPGA Programming complete Trigger mode enabled
Software GUI updated to include all necessary
functionality.
PCB 2 2nd Revision submitted and received. Make sure PCB is working
A/D Filtering implemented as necessary
Timeline – Expo
Scope Working All parts integrated PCB completely tested and connected to FPGA board.
Extras GUI interface updated as time allows
Documentation Completed
USB interface working Data transmitting from FPGA to PC
GUI Sending signals to micro controller Updated graphing capabilities
PCB 2nd revision submitted and tested.
A/D connection to FPGA Data being received and stored
Division of LaborMike
Software – GUI Interface, FPGA Programming USB Interface Assist Josh with microcontroller and Drew with A/D
Jed FPGA Programming Software Interface Assist with A/D converter
Drew A/D converter Microcontroller Interface FPGA Interface
Josh Microcontroller Interface with A/D converter Serial Interface with Computer
Questions ? ? ?