Download Very good – all requirements aptly met. Minor additions/corrections

ECE 477
Digital Systems Senior Design Project
Fall 2008
Homework 9: Software Design Considerations
Due: Friday, October 31, at NOON
Team Code Name: ECE Grande
Group No. 3
Team Member Completing This Homework: Leo Romanovsky
E-mail Address of Team Member: [email protected]
Evaluation:
SCORE
DESCRIPTION
Excellent – among the best papers submitted for this assignment. Very few
corrections needed for version submitted in Final Report.
Very good – all requirements aptly met. Minor additions/corrections needed for
9
version submitted in Final Report.
Good – all requirements considered and addressed. Several noteworthy
8
additions/corrections needed for version submitted in Final Report.
Average – all requirements basically met, but some revisions in content should
7
be made for the version submitted in the Final Report.
Marginal – all requirements met at a nominal level. Significant revisions in
6
content should be made for the version submitted in the Final Report.
Below the passing threshold – major revisions required to meet report
*
requirements at a nominal level. Revise and resubmit.
* Resubmissions are due within one week of the date of return, and will be awarded a score of
“6” provided all report requirements have been met at a nominal level.
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Comments:
ECE 477
Digital Systems Senior Design Project
Fall 2008
1.0 Introduction
The ECE Grand is an integrated No-Limit Texas Hold’em Poker Table system capable of
managing user balance, login authentication and publishing of an ongoing game’s status to a
webpage. A user interface allows players to interact with the game and receive information about
their hands, balances, state of the community cards and various messages. The wide range of
peripherals and complex application logic drives many of the design considerations and
constraints, the details of which are discussed in the remainder of this report.
2.0 Software Design Considerations
Narrowing down the software design considerations began with a thorough analysis of the
project’s functional requirements and use cases. The biggest challenge of the project is the
distributed nature of the computing workflow. The multitier architecture necessary to support
interaction between the master and its slaves required careful consideration of each node’s place
within the system.
The system will support a number of external peripherals and, therefore, system resources,
in order to interface them. The first, the RFID reader, communicates with the Master through a
SCI channel. The second peripheral attached to the Master is the RJ-45 Ethernet jack, and this is
driven by four IO pins. Communication between Slaves and the Master is achieved by over SPI
network. On the Slave, user input is handled by IO pins and the LCD data and commands are
transmitted over a parallel bus.
Out of our functional and resources analysis, the decision to employ an interrupt driven
software structure for both the slave and master was made because of the large number of
supported peripherals. A polling-loop structure would have had the benefit of software simplicity
but may have cause acceptable latency between tasks.
The facility for debugging and testing is crucial to the success of the project for both smooth
development as well as the demonstration of project success criteria. With this in mind, we make
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ECE 477
Digital Systems Senior Design Project
Fall 2008
extensive use of Metrowerks CodeWarrior Processor Expert, centralized software resets and
power-on self tests. By using CodeWarrior’s PE utility, we ensure that all initialization and low
level hardware interaction is handled by the IDE. In addition to this, CodeWarrior’s Simulator
allows for real-time code step-through, breakpoint addition and data monitoring. This has already
proven to be a great asset for tracking down software problems. The other major component of
our debugging strategy is to ensure that all peripherals are fully functional whenever the system
is booted up. We aim to accomplish this by a step-wise reset, beginning with the master and
snaking out to the edges of the system. A master has the capability to reset each slave
individually, which upon reset, are in turn able to reset their associated LCD’s, thus insuring that
all major components, particularly user facing functions, are at a satisfactory level of operation.
Software Design Narrative
System
Enter Game
«uses»
«uses»
Play Game
«uses»
Player
Leave Game
Figure 1: System level use cases
In order to adequately capture our software requirements, both user as well as component
centric views were considered. Design began with a thorough analysis of various user
interactions, before considering the implications of each on the underlying hardware.
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ECE 477
Digital Systems Senior Design Project
Fall 2008
At the lowest level are the peripheral drivers for the LCD and RFID reader. Each of these
provides an interface between the hardware and the system in order to ease the development of
software layers higher in the system stack. Both the RFID and LCD drivers are undergoing
hardware testing. The end goal for the LCD driver is to not only be able to provide an interface
between the system and the device, but to contain a nontrivial graphics library in order to allow
for easier development of simple card representations and text. The LCD driver this ties into a
brief discussion on the user GUI. In order to adequately provide players with the necessary
information to play a game of poker, the LCDs must display a player’s two unique cards, their
balance as well as some options for their possible actions.
The embedded web server [2] [4] is a largely standalone module integrated with the rest of
the system in order to provide the desired functional of publishing a webpage to attached clients.
The core functionality is provided with the open source OpenTCP library, a small footprint
implementation of the TCP/IP protocol aimed at microcontrollers. While lightweight, it is robust
and provides an API at the device driver, socket and application levels. Although the library
supports both TCP and UDP connections, we will only be making use of client requests of TCP.
A successful client to server ping was demonstrated on hardware recently.
Between the application logic and hardware drivers resides the integration software. While
not an explicitly defined region, it is nonetheless a useful final abstraction for tasks needing to
make use of more than one peripheral, and as always to reduce the development costs of the
application logic. One of the primary uses for this layer is to provide an interface between the
master and slave microcontrollers beyond basic SPI drivers. Although the exact protocol is
undeveloped, there is an understanding of the data transmission needs between the devices and at
what points it should occur, with this module ultimately helping to format those packets
appropriately. This layer is in the pseudocode stage.
At the highest level of software in our system resides the application logic required to
manage a poker game. This layer differs dramatically between that present on the master and
slaves. The master will need to perform actions such as deal the proper number of cards to the
right players, manage valid betting (and other user actions) and decide on each rounds winner,
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ECE 477
Digital Systems Senior Design Project
Fall 2008
among other things. Naturally, this layer benefits from being able to have access to highly
abstracted hardware and peripheral models, such as those residing below it. The slave, however,
will be required to perform as much computation as possible internal to minimize the traffic on
the SPI lines. Deciding which actions need additional resources is the primary function of this
layer on the slave. For example, simple updates to the user menu can be refreshed locally. The
current development is in the pseudocode stage.
3.0 Summary
This report detailed the software design constraints of the ECE Grand project, as well as a
thorough description of the purpose and function of each major software component. The state of
driver development is progressing, while the development of the application and integration
logic is proceeding in parallel.
Developing the report serves as a good tool for both outside evaluators as well as being
helpful to the team itself to consider details of the software that were not previously considered.
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ECE 477
Digital Systems Senior Design Project
Fall 2008
List of References
[1] “CFAL12864L-Y-B2,” CrystalFontz, 10/03/2008. [Online] Available:
http://www.crystalfontz.com/products/product.phtml/CFAL12864L-YB2.html?partname=CFAL12864L-Y-B2 [Accessed: October 31, 2008].
[2] “OpenTCP” SourceForge. [Online]. Available: http://sourceforge.net/projects/opentcp/.
[Accessed: October 31, 2008].
[3] “RFID Reader Module,” Parallax. [Online]. Available:
http://www.parallax.com/dl/docs/prod/audiovis/RFID-Reader-v1.1.pdf. [Accessed: October
31, 2008].
[4] S. Torres. "Web Server Development with MC9S12NE64 and OpenTCP," AN2836,
Freescale Semiconductor, 9/2004. [Online]. Available:
http://www.freescale.com/files/microcontrollers/doc/app_note/AN2836.pdf. [Accessed:
October 31, 2008].
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ECE 477
Digital Systems Senior Design Project
Appendix A: Flowchart/Pseudo-code for Main Program
Start
Initialization
Start New Game
and Wait for
Enough Players
Assign Dealer
Chip, Big Blind
and Small Blind
Deal Player Cards
Game Play
Deal Community
Cards
Deal River Card
Game Play
Deal Turn Card
Game Play
Game Play
Decide Winner
Update Balances
Allow Time for
New Players to
Join
Return to Start
Figure 2: System level flowchart
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Fall 2008
ECE 477
Internal
Initialization
Digital Systems Senior Design Project
Verify LCD
Operation
Enter Main
Program Loop
Master Interrupt
Process
Command
Fall 2008
User Interrupt
Request
Additional
Resources from
Master
Update Display
yes
Transmit to
Master?
no
Update Display
Figure 3: Slave Operation
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Process User
Input
ECE 477
Digital Systems Senior Design Project
Fall 2008
Appendix B: Hierarchical Block Diagram of Code Organization
Application
Logic
User Interaction
Integration
Software
LCD
Driver
LCD
Web
Server
RFID
Driver
Server
Application
Logic
RFID Reader
Figure 4: Software Organization
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openTCP
Library