Final Presentation 2004 Momentum Measurement Card (MMC) Project supervised by: Mony Orbach Project performed by: Hadas Preminger Uri Niv.

Final Presentation 2004

Momentum Measurement Card (MMC)

Project supervised by:

Mony Orbach

Project performed by:

Hadas PremingerUri Niv


Introduction The MMC project is a result of

collaboration between the Physics Lab and the HS DSL.

The outcome is an electronic card capable of measuring momentum.

The implementation was done using: FPGA USB to FIFO module. C++ application.


Block Diagram

CycloneFPGA USB

CommunicationUnit

Data

PCB

2 Optical Sensors

Control


The Experiment’s System The experiment

consists of : Two carts on an air

track moving towards each other.

On each cart there is a "Miller Strip“.

Two position sensors.


Input Signals Two 2-bit signals:

Each signal consists of two square waves, with 90° phase difference.

These signals are generated by the two optical encoders (EM-1).

Usb connection to PC.


Output Signals

A file, consists of three dimension array [tick, position1_, position2_].

The length of the array: 600 measurements per experiment (for each cart).

The +/- mark represents the position in reference to the zero point. It is set by the location of the cart in the beginning.


System Rates

Hardware Rates: Main clock rate 12MHz Data transfer rate 32 bits/sample Send/Receive data over USB up to

1Mbits/sec Sampling & Processing rates:

Number of samples per experiment 600 samples Sample resolution 480 counts/inch Sampling Interval (Tick length) 10ms or 5ms

or 3ms Cart minimum/maximum speed 0-5 meter/sec


Currents and Voltages The system uses 3 voltage levels:

5V power supply from the computer via USB cable.

3.3V and 1.5V from an external DC power supply unit of 7.5V. Two internal regulators convert it to the specified voltage levels.

Ground is received from PC.


Current Supply limitations 2 A (for both 3.3V and 1.5V regulators). 500 mA (for the 5V power supply from

the PC). Fuses

Main Fuse – 2A. Pico Fuse – 1A, for the 5V received from

the PC via DLP.

Currents and Voltages – cont.


Electrical Structure

Cyclone

FPGA

Transceivers

DLP

CLK

PCB

EPCSReset

PC

D-9D-15Jack Sockets D-9

sensors


The Connectors D-9 – connection to the EM1 sensors. D-15 – for future use. Jack Sockets – for future connection

of photo-gates. Debag port. JTAG connection for FPGA

programming.


PCB Structure The PCB is made of 6 layers, as

following (from top to bottom): Layer 1 (top) – Signals. Layer 2 – Ground. Layer 3 – Vcc 3.3V. Layer 4 – Vcc 1.5V. Layer 5 – Vcc 5V. Layer 6 (Bottom) – Signals.


PCB Structure – cont. The PCB measurements:

Thickness - 1.6 mm. Length (connectors' side) – 146.1 mm. Width (tracks' side) – 148.7 mm.

PCB's material – FR4.


The FPGA tasks General:

The FPGA has two main tasks: Sample and calculate the position of the cart. Control the data transmission process to the PC.

The two tasks are done by two separate blocks in the implementation and are synchronized by special signals.

2 additional blocks convert the asynchronous input signals to synchronous signals.


Control signal

Inputs’Async

To Sync

Sensor1

Sensor2Calc_Coord

Operating

Machine

ControlSignals

Carts’ coordination

Control’sAsync

To Sync

Control Signals from DLP

DLP Control Signals

DLP8bit DataBus

Data signal

FPGA Top Level


Calc_Coord Block Samples the input

signal and calculates the position of the carts.

Creates the signal ‘Count’.

Determines the direction of the cart.

Counts the number of ‘counts’ from the beginning.

AB

00

01

11

10

L

R


Wave sample0.211 mm

Count

Signal A

Signal B

A xor B


Operating_Machine Block The core of the whole system. It is synchronized with the PC application. Controls of the USB comm. module. Implemented by a Finite State Machine. The blocks main tasks are:

Receiving the sampling interval from the PC. Sampling the counter of the Calc_Coord block

every ‘Tick’. Sending the data to the PC via the USB

module.


Read Byte Cycle

Ready Init_read Read_bus Wait_ RXF1

Wait_ RXF2

Copy Pre_read Wait_ Read

Wait_ Read

RXF_sample2

RXF_smaple1

RD

Data_Buf [7..0]

Data_read [7..0]

Valid

Pre_read Read_bus

Valid

First Byte Second Byte


Write Byte Cycle

Init_write Write_ First

Write_bus Wait1 Wait2 Write_ Second

TXE_sample2

TXE_smaple1

WR

Data_Buf [7..0]

Data_wr [7..0]

Valid

Pre_Write

First Byte Second Byte

Pre_Write Write_bus Pre_Write

Valid


Prior to Power Up When the main power switch is off, and

the USB cable is not connected, the system is in a shut down mode and isolated.

The control lines between the FPGA and the DLP are connected to Pull-Up and Pull-Down resistors to prevent High-Z.

The transceivers are in isolation state until the FPGA competes its Boot-Up sequence.


Power Up Sequence

FPGA Starts its Boot Up Sequence

USB cable connected and main power switch turned on

System Off


Power Up Sequence – Cont.

Transceivers open and set to the right data flow direction.

FPGA sets control lines to appropriate Values .

DLP’s RESET held on ‘0’ level(Disconnected from PC)


Power Up Sequence

A positive edge on the DLP’s signal RESETO indicates that a connection to PC

was successfully established

System Ready

DLP’s RESET set to ‘1’(Enables connection to PC )


Application & Drivers A Visual C++ application was written to:

Establish a real time connection between the peripheral hardware and the PC.

Supply a basic user’s interface. We referred to the USB protocol as a

"Black Box“. The communication between the

hardware and the software is done automatically by the operating system of the PC.


Application & Drivers DLP Design supplies two kinds of

interfaces for the application software developer.

The solution of an Interface that uses a DLL was chosen.


Application & Drivers The

drivers' architecture for the DLL interface are:

Application SoftwareVisual C++

Ftd2xx.dll

Ftd2xx.sys

Operating System – WindowsUSB Driver

Stack

USB245M

The application software is compiled with a .lib file, which connects the application during run-time, to

the .dll file.

Windows USB Interface – via USB stack.

Application Software Interface


Application & Drivers

File NameFile descriptionComments

1.

Ftd2xx.hThis heeder file must be included to the project in order to use the DLP system calls.

The file is one of the files included in the DLL package of drivers.

2.

Function.hIn this header file, the declarations of the utility functions, which are used by main.cpp, are made.

3.

Momentum.hIn this header file, the declarations of the main classes of the program are made.

4.

Function.cppImplementation.

5.

Momentum.cppImplementation.

6.

Main.cppImplementation of the "main" program.


Application’s Flow ChartInitialize USB connection

Is a device connected?

No

Ask user for time between samples

Yes


Application’s Flow Chart

Send time between samples to hardware

Take a sample

600 samples?

No

Yes

End


Application’s Classes Based on two important classes:

Position and DLP. The DLP class manages the

communication between the application and the USB.

The Position class manages and stores the information that is recieved from the hardware.


User Interface


User Interface


User Interface


User Interface


The MMC


Package


Future Improvements Expanding the software to support 2

sets of carts and the photo gates. Allowing the user to determine the

number of measurements per experiment.

Changing the main power switch so it would control also the 5V supply coming from the PC.


Summary Designing a stable reliable system. Designing a PCB.

Final Presentation 2004 Momentum Measurement Card (MMC) Project supervised by: Mony Orbach Project performed by: Hadas Preminger Uri Niv.

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