International Journal of Engineering Trends and Technology (IJETT) – Volume 10 Number 6 - Apr 2014
Station Master Indication Unit
A. Lakshmi Brahmani#1, B. Suresh*2
#
Department of Electronics and communication , K L University
Vaddeswaram, Guntur, AP, India
*
Asst. Professor, K L University
Department of Electronics and communication , K L University
Abstract: To give reliable visual information to the
Station Master about the gate status (OPEN /CLOSE)
of corresponding LC Gates. Closure and opening of the
LC gate is identified using digital input. The digital
input is connected to the Gate logger. Gate logger
transmits this data to Communication unit at station
through modem communication. Communication unit
process the data and controls the tele control relays,
based on the status of Gate. LED based SM indication
unit is located on the top of the SM panel. Based on the
Gate Status, Red led will be on for Gate Open and
Green led for Gate Close.
whenever System fail occurs and to stop the buzzer, switch
is provided for acknowledge the failure.
Keywords: LC gates, Accident avoidance.
I. INTRODUCTION
Station Master performs the actions regarding train
passage from station based on the information he received
from Gate man for non-interlocked gates. In
Non-Interlocked LC Gates, Station master share the a
private number with gate man to close the gate. When
corresponding Gate is closed, station master receives a
private number from gate man declaring that he closed the
gate, and Station master clear the Last Stop Signal(LSSgreen). Then loco pilot starts the train and train leaves the
station. In this scenario (private number exchange process)
station master blindly believes the gateman without any
validated evidence. So Station Master Indication Unit is
provided to represent actual gates status such that the
chance of occurring human errors due to lack of
communication between station master and gate man could
be reduced.
II. R EQUIREMENTS:
A. Functional Requirements :
Station Master allows the train if and only if
Non-interlocked LC gates status was closed. So Station
master needs the knowledge of LC Gates status. For this
SM Indication unit provides status of eight gates at a time
at a single station. Gate indications are given as follows
1. RED for Gate opens.
2. GREEN for Gate close.
3. YELLOW if Gate status is unknown.
System failure alarm is required to station master
ISSN: 2231-5381
Figure 1: Structure of LC Gates.
B. System Requirements :
System needs one Communication Unit (CU) port
to communicate with CU in the following aspects.
1. Receiving command packet.
2. Sending acknowledgment packet.
1)
Receiving command packet :
Station Master Indication Unit performs its
actions based on the command packet sent by CU. So
Station Master Indication Unit needs continuous
receiving command packet from CU.
2)
Sending acknowledgment data packet :
For every minute acknowledgment packet is send by
SM Indication unit to CU to give its status.
To perform above functionalities, UART1 with baud rate
9,600 bits/seconds, no parity bit and 1 stop bit is needed for
communicating with CU. And CU port uses 485
communications to support long distance communication.
Also, to identify corresponding LC gates status station
master needs
1. Red LED indicates Gate is open.
2. Green LED indicates Gate is closed.
3. Yellow LED indicates Gate status is unknown.
MBI _Driver (5039) is used to drive all gates status
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International Journal of Engineering Trends and Technology (IJETT) – Volume 10 Number 6 - Apr 2014
indication LEDs, since single LED at a time can drive
maximum 16 LEDs. To identify the faults Station Master
requires
1. Buzzer to generate alarm when system fails.
2. Switch to stop the buzzer.
Hard ware consists of LPC2103 controller, 24v to 5v
DC - DC converter, 3.3v regulator, 1.8v regulator,
5039MBI_drivers,
Mono-shot,
Relay,
556Timer,
Acknowledgment switch, Full Duplex RS 485 and LEDs.
LPC 2103 is programmed to control all other hard ware
modules. MBI5039 is an enhanced 16 channel constant
current LED sink driver. So one MBI driver at a time can
control 16 LEDs .In this circuit two MBI drivers are used
to drive total 24 (8 RED + 8 GREEN+8YELLOW) 10mm
Indication LEDs, based on the input signals. Mono shot
circuit is continuingly fed with low to high input used to
generate an high level pulse till the processor is working
and produces low on output signal when processor is not
working. Relay is used to drive the System OK LED,
System FAIL LED and 556Timer. When processor is
working normally, relay output pins are connected to NC,
so that System OK LED is driven, and when processor is
not working relay output is connected to NO so that
System FAIL LED is driven and System fail buzzer pin of
556 timer is becomes high and 556 timer is operated in
astable mode. When system fails 556timer is operated in
astable mode and generates the frequency 1.45 KHz so that
Alarm is operated with the same frequency. When
Acknowledgment switch is pressed timer comes to reset
position and alarm is stopped. Full Duplex RS 485 is used
for 485 communications which support long distance
communication. Health LED (green smd LED) is directly
controlled by LPC 2368. 3.3v supply is directly given to
Power on LED (yellow smd LED) so that it glows when
there is a continuous supply of 3.3volts.
III. TEST SET UP
Debugger port uses UART0 with baud rate 9,600
bits/seconds, no parity bit and one stop bit used to dumping
the code into hard ware. CU port uses UART1 with baud
rate 9,600 bits/seconds, no parity bit and 1 stop bit used to
receive the command packet from workstation and to send
acknowledgment packet to work station. TALK_50mb soft
ware must be configured to particular port settings. Using
TALK_50mb soft ware we can send the packets to SM
indication unit and we can view the received data.
IV. ARM PROGRAMMING
Microprocessors and micro controllers are widely
used in embedded systems products. Micro controller is a
programmable device. A micro controller has a CPU in
addition to a fixed amount of RAM, ROM, I/O ports and a
timer embedded all on a single chip. The fixed amount of
on-chip ROM, RAM and number of I/O ports in micro
controllers make them ideal for many applications in which
cost and space are critical."LPC 2368" is an ARM
(ADVANCED REDUCED INSTRUCTION SET) based
micro controller. It has high performance, low power
consumption and it takes a small amount of the available
silicon die area.
V. UNIVERSAL ASYNCHRONOUS
RECEIVER/TRANSMITTER
There are two methods for serial communication,
Synchronous & Asynchronous.
A. Synchronous serial communication:
In Synchronous serial communication the
receiver must know when to “read” the next bit
coming from the sender, this can be achieved by
sharing a clock between sender and receiver. In
most forms of serial Synchronous communication,
if there is no data available at a given time to
transmit, a fill character will be sent instead so
that data is always being transmitted. Synchronous
communication is usually more efficient because
only data bits are transmitted between sender and
receiver; however it will be more costly because
extra wiring and control circuits are required to
share a clock signal between the sender and
receiver.
Figure 2: SM Indication unit
ISSN: 2231-5381
B. Asynchronous serial communication:
Asynchronous transmission allows data to
be transmitted without the sender having to send a
clock signal to the receiver. Instead, special bits
will be added to each word in order to synchronize
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International Journal of Engineering Trends and Technology (IJETT) – Volume 10 Number 6 - Apr 2014
the sending and receiving of the data. When a
word is given to the UART for Asynchronous
transmissions, a bit called the "Start Bit" is added
to the beginning of each word that is to be
transmitted. The Start Bit is used to alert the
receiver that a word of data is about to be sent,
and to force the clock in the receiver into
synchronization with the clock in the transmitter.
C. Baud rate:
Baud rate is a measurement of transmission
speed in asynchronous communication. It
represents the number of bits that are actually
being sent over the serial link. The Baud count
includes the overhead bits Start, Stop and Parity
that are generated by the sending UART and
removed by the receiving UART.
provides a status code that denotes the priority and
source of a pending interrupt. The interrupts are
frozen during an UIIR access. If an interrupt
occurs during an UIIR access, the interrupt is
recorded for the next UIIR access.
G. UART FIFO Control Register: The UFCR
controls the operation of the UART Rx and TX
FIFOs.
H. UART Line Control Register:
The
ULCR
determines the format of the data character that is
to be transmitted or received.
I.
VI. REGISTER DESCRIPTION
UART Line Status Register: The ULSR is a
read-only register that provides status information
on the UART TX and RX blocks.
A. UART Receiver Buffer register: The UART
Receiver Buffer Register contains the oldest
J.
UART Transmit Enable Register: UTER enables
implementation of software flow control. When
received byte in the UART Rx FIFO.
TXEn=1, UART transmitter will keep sending
B. UART Transmit Holding Register: Writing to the
UART Transmit Holding Register causes the data
data as long as they are available. As soon as
TXEn becomes 0, UART transmission will stop.
to be stored in the UART transmit FIFO. The byte
will be sent when it reaches the bottom of the
VII. PROGRAMMING ON KEIL SOFTWARE
FIFO and the transmitter is available.
C. UART Divisor Latch registers: The UART Divisor
Latch LSB Register, along with the UDLM
register, determines the baud rate of the UART.
The UART Divisor Latch MSB Register, along
with the UDLL register, determines the baud rate
of the UART.
D. UART Fractional Divider Register: The UART
Fractional Divider Register (UFDR) controls the
clock pre-scaler for the Baud rate generation and
can be read and written at the user’s discretion.
This pre-scalar take the APB clock and generates
an output clock according to the specified
fractional requirements.
E. UART Interrupt Enable Register: The UIER is
used to enable UART interrupt sources.
F. UART Interrupt Identification Register: The UIIR
ISSN: 2231-5381
µVision is a window-based software development
platform that combines a robust and modern editor with a
project manager and make facility tool. It integrates all the
tools needed to develop embedded applications including a
C/C++ compiler, macro assembler, linker/locator, and a
HEX file generator. µVision helps expedite the
development process of embedded applications by
providing the following:
A. Full-featured source code editor.
B. Device Database for configuring the development
tool.
C. Project Manager for creating and maintaining your
projects.
D. Integrated Make Utility functionality for assembling,
compiling, and linking your embedded applications.
E. Dialogs for all development environment settings.
F. True integrated source-level and assembler-level
Debugger with high-speed CPU and Peripherals.
G. Advanced GDI interface for software debugging on
target hardware and for connecting KEIL ULINK
Debugger.
H. Flash programming utility for downloading the
application program into Flash ROM.
I. Links to manuals, on-line help, device data-sheets,
and user guides
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International Journal of Engineering Trends and Technology (IJETT) – Volume 10 Number 6 - Apr 2014
VIII. CONCLUSION
Ability to identify entry/exit of train towards Unmanned
Level Crossing. Ability to identify Speed & Direction of
train. Wireless transmission of data from Sensor Modules
to Master Modules. Audio & Visual alerts to road users
about approaching train. Energy harvesting. Also we are
not changing the actual process but we are increasing the
effectiveness of the process so that station master can take
his own decisions with out blindly believing the gate man.
ACKNOWLEDGMENT:
It is with immense gratitude that I acknowledge the
support and help of my Professor Mr. B. Suresh and also I
am indebted to my parents and my classmates for helping
me to complete this thesis.
REFERENCES
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http://www.keil.com/dd/docs/datashts/philips/lpc23xx_um.pdf
http://www.mblock.com.tw/products.php?KindID=1&ID=16
http://www.datasheet.co.kr/datasheet-html/C/M/X/CMX869_CML
Microcircuits.pdf.html
http://www.rdso.indianrailways.gov.in/works/uploads/File/41_00.p
df
http://www.efftronics.com/Railway_Signaling/LC_Gate_Warning_
System_for_Manned_Interlocked_Gate.php
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