Transcript Document 7301309

Design of Bluetooth
interface for low cost
embedded system.
Brett Carter
BDS(Hons)
ID: 18151515
Supervisors:
Charles Greif, Dr. Tim Ferguson.
22/05/2016
1
Overview



Reason for the project
Applications
Background
• Wireless communications
• Embedded device




System design
Functionality
Simulation and testing
Future work
22/05/2016
Brett Carter, BDS(Hons)
2
Reason for the project


There is an increasing desire to perform computing tasks
“on the move”.
Wireless access of large data stores is cheaper than
carrying all the information with you.
22/05/2016
Brett Carter, BDS(Hons)
3
Applications
Hand-held web browsing
 Synchronization of Personal
organizer
 Multiplayer gaming

22/05/2016
Brett Carter, BDS(Hons)
4
Background

Gameboy Advance
(GBA)




22/05/2016
16Mhz ARM CPU on
board
Very little Random
Access Memory
Reads and executes
code on an
expansion card
(cartridge)
Graphical User
Interface
Brett Carter, BDS(Hons)
5
Background

Why GBA?
• Software tools freely available
• Inexpensive
• Color graphical interface
22/05/2016
Brett Carter, BDS(Hons)
6
Background

Bluetooth
• Transmits on the 2.4 GHz
industrial, scientific, and
medical (ISM) band
• Range of 10/100 meters
• Single chip designs
22/05/2016
Brett Carter, BDS(Hons)
7
Background

Why Bluetooth?
• Allows quick establishment and disconnection
of a link
• Inexpensive
• Low Power
• ISM band Does not require a license
• Avoids noise by frequency hopping
22/05/2016
Brett Carter, BDS(Hons)
8
System Design
Cartridge for GBA
Must fit GBA form factor
 Non Volatile Memory for applications
 Wireless link to download data
 Control Hardware

22/05/2016
Brett Carter, BDS(Hons)
9
System Design
Crystal
Oscillator
Flash
RAM
Bluetooth
Device
16
24
UART
Serial
PROM
FPGA
CPLD
J
T
A
G
J
T
A
G
24
24
GBA Bus
22/05/2016
Brett Carter, BDS(Hons)
10
GBA Bus

24bit multiplexed address data bus
• 24bit address
• 16bit data



Asynchronous memory access
Random and sequential memory reads
Software enabled clock signal
22/05/2016
Brett Carter, BDS(Hons)
11
GBA Bus
22/05/2016
Brett Carter, BDS(Hons)
12
GBA Bus
22/05/2016
Brett Carter, BDS(Hons)
13
Bluetooth Module



Requires 12Mhz Crystal Oscillator
Handles profiles, connect/disconnect
Passes received data through UART
22/05/2016
Brett Carter, BDS(Hons)
14
FPGA controller





Xilinx Spartan XS10XL
Receives Serial data and makes it available for storage
Acts as a pseudo-memory location
De-multiplexes Address bus
Volatility means the device must be reprogrammed at
power-up or boot from a serial ROM
22/05/2016
Brett Carter, BDS(Hons)
15
FPGA controller
UART
Shift register
Serial
PROM
JTAG
Buffer
A23
D0-D15
22/05/2016
Brett Carter, BDS(Hons)
16
CPLD controller




Altera EPM3064
De-multiplexes (latches) address/data bus
Increments address for sequential access
Allows boot-up application to be flashed
• Through UART link from PC
• By Flash writer via the GBA Bus
22/05/2016
Brett Carter, BDS(Hons)
17
CPLD controller
A0-A23
Buffer
UART
Counter/Latch
From PC
Shift
register
JTAG
A0-A23
22/05/2016
Brett Carter, BDS(Hons)
18
CPLD controller

Transmission protocol for loading boot-up
application to memory through UART:
1 Word write to Address $123456
------$C1--$12--$34--$56--DataHi--DataLo------
256 Word write From Address $123456
----$D2--$12--$34--$56--Data0Hi--Data0Lo--Data1Hi--Data1Lo--…
22/05/2016
Brett Carter, BDS(Hons)
19
Flash Memory





Toshiba/Intel Strata flash
Non Volatile
65ns access time
128Mbit (8Mx16 bits)
Slow, difficult writing
22/05/2016
Brett Carter, BDS(Hons)
20
Software tools

VSIM - VHDL simulator
• Simulate firmware incrementally
22/05/2016
Brett Carter, BDS(Hons)
21
Software tools

Mentor DesignView
• Schematic design

Mentor Expedition PCB
• Routing Printed circuit board
22/05/2016
Brett Carter, BDS(Hons)
22
Software tools
22/05/2016
Brett Carter, BDS(Hons)
23
Functionality


Initially run default (boot-up) application,
or an application received in a previous
session
Establish an Ad Hoc link
• PC user transmits new application/game over
the link
• Application gets stored in Flash RAM


Data to be processed can also be transmitted
Close link and execute application
• Application remains in flash RAM after power is
removed
22/05/2016
Brett Carter, BDS(Hons)
24
Conclusion
Prototype design satisfies
specifications and is ready to be
manufactured
 In house Manufacturing was not
possible due to circuit complexity.

22/05/2016
Brett Carter, BDS(Hons)
25
Future Work

Manufacture and populate PCB
• Synthesize all VHDL
Create Boot-up application/menu
 Implement flow control for UART
transceiver

• Allows for higher speeds
22/05/2016
Brett Carter, BDS(Hons)
26
References
http://www.ziegler.desaign.de/GBA/g
ba.htm
 http://www.bluetooth.org
 http://www.bluetooth.com
 http://www.gbadev.org

22/05/2016
Brett Carter, BDS(Hons)
27