A Performance Analysis System for the Sport of Bowling

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$Course Syllabus - Penn State Harrisburg Math/Computer Sciences ...$

$A Simulator for the MARIE Architecture - Penn State Harrisburg Math ...$

2.7.8 Communication with the COMM Wand Communications with the module are conducted over a wireless, infrared (IR) interface, using the TSL251 as the receiver, and two surface-mount LED's as the transmitter. Since the 87C752 does not contain an on-board hardware UART, a software UART has been implemented. The software UART conforms to several design constraints specific to the SMARTDOT module hardware. Baud Rates: Due to the limited response time of the TSL251, and the relatively slow conversion rate of the '752's ADC at the module's clock frequency, reliable reception is only possible up to 600 baud. The communication protocol between the module and the COMM wand is designed such that the module normally receives single character transmissions from the wand. Consequently, the 600 baud reception rate does not create a communications bottle-neck. Since the COMM wand can receive at a much higher baud rate than the SMARTDOT module, the module transmits to the COMM wand at up to 38400 baud (another limitation imposed by the module's clock frequency). Data Frame: A 12-bit serial protocol is used on transmission: 1 START bit, 8 DATA bits, 1 PARITY bit (EVEN), and 2 STOP bits. An 11-bit protocol (using a single STOP bit) is used for reception. This imbalance in STOP bits guarantees a minimal extra dead space between back-to-back characters, and allows for clock skew between the module and the COMM wand. Bit Sampling: The TSL251 and the 87C752's ADC are used for serial reception. The light waveform is sampled at 4800 Hz (8 samples per bit time), and the middle four samples of each bit determine the value (0 or 1) for that bit. Ignoring the first two and last two bit samples allows for some clock skew between the transmit baud rate of the COMM wand and the receive baud rate of the module. A count of two or more DARK middle samples constitutes a logical '1', otherwise the bit is considered a logical '0'. The bias is toward the DARK samples since the COMM wand's presence over the finger insert creates a dark ambient condition. As long as the COMM wand is held relatively close to the insert, the background remains dark enough for the module to discriminate between the light pulses (0's), and the ambient background level (1's). A noise margin is also built into the bit-sampling scheme. There is a gap established between the DARK and LITE levels, with the transition point switched between the two depending on the value of the last sample received, creating a digital hysteresis function. Refer to Figure A-7 (UART Receive Task Flowchart) and Figure A-8 (Bit Sample ISR Flowchart). 2.7.9 Communication Protocol All communications with the module are initiated by pressing on the insert, and then placing the COMM wand over the insert, covering the opening. The bowler has one second to remove their finger from the insert, and another second following release to cover the insert with the COMM wand. If either of these conditions is not met, the module shuts down and must be reactivated. Upon activation, the module waits for release to occur, as previously described. When it identifies a release condition, it looks for a valid waveform. In the case of a COMM wand transmission, the module discovers that the ball is not rolling within 600 msecs (through the discrimination and validation routine), switches to the COMM wand detection routine, and waits for up to one second for the insert to become dark (become 26
covered by the wand). When the module detects the appropriate level of darkness, it assumes the COMM wand is in place, and transmits a specific "HI" character to the wand. An ASCII 'U' (0x55 - 01010101b) is used as the "HI" character because it requires an alternating light level of 38400 Hz to be detected, which is highly unlikely to occur under ambient light conditions. If the COMM wand is actually in place over the insert, it receives the "HI" character, and responds with a NULL character at 600 baud. The NULL character (0x00) appears to the module as a light pulse of a fairly precise length (~16.7 msec - 10 consecutive '0' bit times, including the START bit and the EVEN parity bit) in an otherwise dark ambient background, another condition that is unlikely to occur under ambient conditions. The module waits for up to 200 msecs to receive the COMM wand's acknowledgment. If the module does not receive a valid acknowledgement light pulse within this time, it retransmits the "HI" character, and waits for the COMM wand's response. The module tries to contact the COMM wand three times before assuming the wand is not present, at which time it shuts down. Refer to Figures A-5 (Communication Task Flowchart), A-6 (Wand Detection ISR Flowchart), and A-9 (Receive Time Out ISR Flowchart). If the module receives a valid light pulse, it transmits another "HI" character to the COMM wand, at which point a "conversation" ensues between the SMARTDOT module and the COMM wand. If the protocol fails at anytime, or a reception error is detected, the module aborts the conversation and tries to reestablish communications with the COMM wand from the beginning, for a total of three attempts, before finally shutting down. 2.7.10 Commands The MASTER program can issue various commands through the COMM wand to the module to retrieve data, to select the module's sampling mode, and to configure certain module parameters shown in Figure 2-5a. Before the bowler can view the waveform the SMARTDOT module has captured, the MASTER must upload that data from the module by issuing the TRANSMIT command, which instructs the module to transmit the contents of its data memory. As an example, the protocol for uploading data from the module to the MASTER is: MODULE: "HI" 'U' (0x55) @ 38400 baud - "Are you there?" MASTER: NULL 0x00 @ 600 baud - "I'm Here" MODULE: "HI" 'U' (0x55) @ 38400 baud - "Clear to Send" MASTER: 'T' "Transmit" mnemonic @ 600 baud MODULE: 'T' Echoed back to MASTER @ 38400 baud MASTER: 'XON' 0x11 @ 600 baud, MASTER is ready to receive data MODULE: EEPROM contents 512 bytes @ 38400 baud To accommodate baud rate switching in the MASTER, the SMARTDOT module inserts a delay between each reception from the MASTER and subsequent transmission to the MASTER. Including the delays, the entire upload process still takes less than a second. Appendix C includes timing diagrams for the individual command protocols: Figures C-1 (Upload Command), C-2 (Mode Command), and C-3 (Configuration Command). 27
Page 1 and 2: The Pennsylvania State University T
Page 3 and 4: TABLE OF CONTENTS Section I: Introd
Page 5 and 6: LIST OF FIGURES Figure 2-1 SMARTDOT
Page 7 and 8: SECTION I: INTRODUCTION, BACKGROUND
Page 9 and 10: eceiver that stores, processes, and
Page 11 and 12: 1.3.2 Product Development Phase The
Page 13 and 14: SECTION II: COLLECTING THE DATA - T
Page 15 and 16: 2.2 Design Constraints The feasibil
Page 17 and 18: 2.3 SENSING REQUIREMENTS The module
Page 19 and 20: Pin Deck Light Foul Line Figure 2-2
Page 21 and 22: 2.4.1 Ambient Light Sensor The ambi
Page 23 and 24: 9 28 8 RST V CC V CC 5 6 hyst 7 3 +
Page 25 and 26: 2.6 HARDWARE/SOFTWARE INTERACTION D
Page 27 and 28: 2.6.3 Baud Rate The module communic
Page 29 and 30: Configuration settings and the samp
Page 31: 2.7.5 The Ball is Rolling If the wa
Page 35 and 36: 2.8.1 Detecting Release Detecting t
Page 37 and 38: Light Level 100 90 80 70 60 50 40 3
Page 39 and 40: By filtering the data, and then cou
Page 41 and 42: The 'F300x can write to any portion
Page 43 and 44: One possibility is to use a transfo
Page 45 and 46: 2.10 SUMMARY This portion of the re
Page 47 and 48: The ball's angular velocity increas
Page 49 and 50: Light Level 100 90 80 70 60 50 40 3
Page 51 and 52: the fundamental frequency has been
Page 53 and 54: Since the fundamental frequency and
Page 55 and 56: Figure 3-7: MASTER "Analysis" Scree
Page 57 and 58: known, the linear momentum (and thu
Page 59 and 60: In order to find the value for v 1
Page 61 and 62: 3.5 ASSUMPTIONS AND ERROR ANALYSIS
Page 63 and 64: 3.5.3 External Forces and Friction
Page 65 and 66: 3.6.1 Implementation and Performanc
Page 67 and 68: Figure 3-11a: Effects of Phase Shif
Page 69 and 70: 3.6.3 The "Perfect" Game to Analyze
Page 71 and 72: Since the change in angular velocit
Page 73 and 74: BIBLIOGRAPHY [1] United State Paten
Page 75 and 76: APPENDIX A - SMARTDOT MODULE EMBEDD
Page 77 and 78: Appendix A: SMARTDOT Module Embedde
Page 83 and 84:
Appendix A: SMARTDOT Module Embedde
Page 85 and 86:
APPENDIX B - SMARTDOT MODULE SOURCE
Page 87 and 88:
Appendix C: SMARTDOT Module Command
Page 89 and 90:
Figure C-3 Appendix C: SMARTDOT Mod
Page 91 and 92:
APPENDIX E - 300 GAME MASTER SCREEN
Page 93 and 94:
Appendix E: 300 Game Analysis Frame
Page 95 and 96:
Page 97:
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A Performance Analysis System for the Sport of Bowling

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