Download Mid Semester Presentation - High Speed Digital Systems Laboratory

Technion - Israel institute of technology
department of Electrical Engineering
High speed digital systems laboratory
‫ מכון טכנולוגי לישראל‬- ‫הטכניון‬
‫הפקולטה להנדסת חשמל‬
‫מעבדה למערכות ספרתיות מהירות‬
Midterm Presentation
Transfer fax over IP
in cellular networks
Performed by: Carmel Yuval, Mishael Avihoo
Instructor: Orbach Mony
Cooperated with: Qualcomm Israel
High speed digital systems laboratory
‫המעבדה למערכות ספרתיות מהירות‬
Project Goal
Transmit fax page from a fax machine to
a computer and receive a fax page from a
computer to a fax machine.
‫המעבדה למערכות ספרתיות מהירות‬
High speed digital systems laboratory
Block Diagram
Control/
feedback
Fax
SLIC
DSP
Computer
High speed digital systems laboratory
‫המעבדה למערכות ספרתיות מהירות‬
Functional Description
• Converting analog fax transmission to a digital signal
• Decoding and interpreting the digital signal
• Determine the fax call state from the digital signal using state
machine, negotiating accordingly with the computer
• Transmitting an image information to the computer using ATCommands
• Repeating the process for the case of the computer initiating
the fax call
‫המעבדה למערכות ספרתיות מהירות‬
High speed digital systems laboratory
Interfaces
SCLK
CS
SDI
SDO
ProSLIC
SCLK0
DRX
PCM
DT0
DTX
PCM
DR0
FSYNC
Parallel Interface
ADSP-2181
RFS0
EZ-ICE
Evaluating
Board
DT1
CONTROL
PC
DR1
EZ-KIT
LOCAL
FAX
Analog
PCLK
RS-232
PC
EMULATE
IWF
High speed digital systems laboratory
‫המעבדה למערכות ספרתיות מהירות‬
Interfaces (cont.)
• ProSLIC
• Parallel port – to controller (computer).
• Analog – to phone line (200-2200Hz).
• Serial – PCM digital signal to DSP (2.048MHz).
• DSP
• Serial RS-232 – to PC emulating IWF (4800-19200bps).
• EZ-ICE – for debugging DSP (9600bps).
• Serial – PCM digital signal to ProSLIC (2.048MHz).
‫המעבדה למערכות ספרתיות מהירות‬
High speed digital systems laboratory
Data Rates and Bandwidths
Place
Rate / Frequency
Input (Phone Line)
200-2200Hz
Output (RS-232)
4800 - 19200bps
PCM interface
2.048MHz
DSP clock
20MHz
PCM Sampling Rate 8KHz
High speed digital systems laboratory
‫המעבדה למערכות ספרתיות מהירות‬
Built In Tests
• Program debugging
• Using VisualDSP+EZ-ICE.
• Log points – TBD.
•ProSLIC
• Power on – Power LEDs.
• Computer interface – Using program.
• Phone line interface – Tone generation, using fax.
• PCM interface – TBD.
High speed digital systems laboratory
‫המעבדה למערכות ספרתיות מהירות‬
Built In Tests (cont.)
• DSP
• Power on – Power LEDs.
• Computer interface – TBD.
• PCM interface - TBD.
• EZ-ICE interface – TBD.
‫המעבדה למערכות ספרתיות מהירות‬
High speed digital systems laboratory
Complete System Overview
PSTN
IWF
MSC
FAX
BSC
BTS
MS
HOST DSP
FAX
High speed digital systems laboratory
‫המעבדה למערכות ספרתיות מהירות‬
Complete System Overview (cont.)
• MS – Mobile Station - Wireless communication device,
contains the DSP, interfaces the fax to the cellular network.
• BTS – Base Transceiver Station – Connects the MS to the
cellular network using wireless interface.
• BSC – Base Station Controller – Controls Resources.
High speed digital systems laboratory
‫המעבדה למערכות ספרתיות מהירות‬
Complete System Overview (cont.)
• MSC – Mobile Switching Center – The cellular network
PSTN.
• IWF – Inter Working Function – Connects the cellular
network to PSTN using modems (Dial up, fax, etc.).
• PSTN – Public Switching Telephone Network – connects
subscribers.
High speed digital systems laboratory
‫המעבדה למערכות ספרתיות מהירות‬
Project’s Alternatives
• External Modem – Of the shelf solution, cheap, but large, can
not generate PSTN functions.
• Canceling Vocoder (voice compression algorithm) – Not
supported.
‫המעבדה למערכות ספרתיות מהירות‬
High speed digital systems laboratory
ProSLIC
• Provides a complete analog telephone interface.
• “Subscriber Line Interface Circuit”.
• codec.
• DTMF functions.
• Signal generation functions (linefeed).
• Consist A/D, D/A, DC to DC converter, programmable signal
generator, signal detector and much more on one chip.
High speed digital systems laboratory
‫המעבדה למערכות ספרתיות מהירות‬
ProSLIC (cont.)
• codec (coder decoder):
• Convert analog signal to PCM.
• Convert PCM to analog signal.
• Comply with A-Law, μ-Law.
High speed digital systems laboratory
‫המעבדה למערכות ספרתיות מהירות‬
ProSLIC (cont.)
• DTMF functions:
• “Dual Tone Multi Frequency”.
• Two frequency generators for generating DTMF signals.
• DTMF detection.
High speed digital systems laboratory
‫המעבדה למערכות ספרתיות מהירות‬
ProSLIC (cont.)
• Linefeed:
• on-hook voltage.
• off-hook loop current.
• on-hook transmission ringing voltage.
High speed digital systems laboratory
‫המעבדה למערכות ספרתיות מהירות‬
DSP Software
• The project consist of written program which works with a
host processor.
• The written software will be alternated in order to disable the
host interface.
High speed digital systems laboratory
‫המעבדה למערכות ספרתיות מהירות‬
DSP Software (cont.)
Interrupts
IWF
DSP
HOST
DPR
(SM)
High speed digital systems laboratory
‫המעבדה למערכות ספרתיות מהירות‬
DSP Software (cont.)
• The host and the DSP shares RAM for exchange commands
and data.
• When the host or the DSP puts new data at the shared
memory, they initiates interrupt to inform the other side about
the new data.
High speed digital systems laboratory
‫המעבדה למערכות ספרתיות מהירות‬
DSP Software (cont.)
DSP
DPR
(SM)
PC
Interrupts
Host
Module
‫המעבדה למערכות ספרתיות מהירות‬
High speed digital systems laboratory
DSP Software (cont.)
• The host module is a software function in the DSP.
• The host module will connect the DSP to the PC (IWF) via
RS-232 (SPORT1).
• The module will acts as the host when reading and writing
into the shared memory.
• The module will initiate interrupts to the DSP and respond to
such.
DSP
DPR
(SM)
PC
Interrupts
Host
Module
High speed digital systems laboratory
‫המעבדה למערכות ספרתיות מהירות‬
Timetable
Week
Duty (Avihoo)
Duty (Yuval)
28/12 – 1/1
EZ-ICE Setup
11-15/1
DSP Integration
(Software)
Old Program
Integration
Writing Module
18-22/1
Writing Module
ProSLIC issues
25-29/1
Writing Module
Interrupt handling
4-8/1
Hardware
Integration
PC Interface