Flat ribbon cables (FRC) are used now days in all industrial and IT
applications. They come in 10 to 42 pins connector. In industries they are
manufacturing in huge lot, and need to be passed out from quality check. As it is
not possible to check every pins with normal meter & also it takes too much
time. In market, some FRC TESTERS are available which test only continuity
and give output via a simple led or lcd without any description. Checking only
continuity is not enough to examine quality and performance of FRC, neither in
production nor in maintenance.
As time being, any loose contact or partially damaged cable generates a
big problem which cannot be rectified in continuity tester. The testers available
in the market can check only wiring continuity, opens-shorts and mis-wiring.
They compare transmitted and received data between the two ends of the cable
and the result is shown by LEDs.
But, here I know the importance of self resistance of the cable or any miscrimping
occurred during the production of FRC. This resistance creates
problems while passing a sensitive signal or waveforms.
So, I am going to design a tool to test the FLAT RIBBON CABLE
accurately and immediately measure the voltage drops between two ends of
FRC and will generate a full test report with the identification of faulty & ok
pins having 0 & 1 binary respectively and will execute it to PC via a COM port.
This binary value will show actual performance of particular cable either
it is reliable or not. As, this error which cannot be ever detected in any tester, I
am challenging until now there is no any tester available with above features.
1
Chapter 1:-Introduction
1.1 Problem Summary :
Flat ribbon cables are used now days in all industrial and IT applications. They
come in 10 to 42 pins connector. In industries they are manufacturing in huge lot and
need to be passed out from quality checking. As it is not possible to check every pins
with normal meter & also it takes too much time which never fulfills the demand of
market with time and quality. In market, some FRC TESTERS are available which
test only continuity and give output via a simple LED or LCD without any
description.
Figure 1 – Flat Ribbon Cable
Checking only continuity is not enough to examine quality and performance of
FRC, neither in production nor in maintenance. As we know, every material has its
own resistance in terms of its purity or impurity.
Here, I know the importance of self resistance of the cable or any miscrimping
occurred during the production of FRC. Any tester available in the market
can check only continuity but can’t measure or show the perfect value of resistance
for FRC. This resistance creates problems while passing a sensitive signals or
waveforms.
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1.2 Purpose Of The Project :
At HHPE (Hitachi Hi-Rel Power Electronics), IGBT and Thyristors are being
used which need gate pulse to drive. These pulses are sending through FRC from one
card to another. As time being, any loose contact or partially damaged cable generates
a big problem which cannot be rectified in continuity tester.
The testers available in the market can check only wiring continuity, opensshorts
and mis-wiring. They compare transmitted and received data between the two
ends of the cable and the result is shown by LEDs.
But, here I am going to design a tool to test the FLAT RIBBON CABLE
accurately. It will immediately measure the dropped voltage between two ends of
FRC and will generate a full test report with the detection of faulty & ok pins having
0 & 1 binary respectively and will execute it to pc via a com port.
This binary value will show actual performance of particular cable either it is
reliable or not. As, this error which cannot be ever detected in any tester, I am
challenging until now there is no any tester available with above features.
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Chapter 2:- Brief History Of Work
2.1 Block Diagram :
Figure 2 – Block Diagram
FLAT
RIBBON
CABLE
POWER
SUPPLY
SWITCHING
IC
DECODER
NOT GATE
PIC
CONTROLLER
RS-232
MODULE
PC
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2.1.1 Power Supply :
As shown in block diagram, 5 ICs are used & all digital ICs are driven with
DC supply. Switching IC is driven with +12V input supply, while all other ICs such
as NOT Gate, Decoder, PIC Controller & Max-232 are driven with +5V input Supply.
Also, FRC is connected with +5V input supply for the measurement purpose. So, here
we have used 2 separate power supply circuits ‘ one for +5V supply & another for
+12V supply.
Transformer is used to step down 230V AC mains & we can get 6-12V ac.
These voltages can be converted into 5V using LM7805 IC, where to convert it into
12V, LM7812 IC is used. Both ICs are 3 terminal positive voltage regulators.
The DC power is obtained from a bridge rectifier circuit which can be
connected to the transformer. Transformer is directly connected to the ac mains to
give step down ac voltage to the bridge circuit. The voltage is brought down to the
desired level using full wave rectifiers and voltage regulators.
It also contains current-limiting circuitry and thermal overload protection, so
that the IC won’t be damaged in case of excessive load current; it will reduce its
output voltage instead.
Figure 3 – Power Supply Circuit
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2.1.2 Switching IC :
The MAX4662 quad analog switches feature low on-resistance of 2.5A max.
On-resistance is matched between switches to 0.5A max and is flat (0.5A max) over
the specified signal range. It can handle rail-to-rail analog signals. This analog switch
is ideal in low-distortion applications and is the preferred solution over mechanical
relays in automatic test equipment or applications where current switching is required.
It has lower power requirements, use less board space, and are more reliable than
mechanical relays.
It has four normally open (NO) switches. This device operates from a single
+4.5V to +36V supply or from dual ??4.5V to ??20V supplies. A separate logic supply
pin guarantees TTL/CMOS-logic compatibility when operating across the entire
supply voltage range.
Figure 4 – Pin Diagram Of MAX4662
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Here, MAX4662 is operated with +5V single supply. Each pin of FRC is
connected to data pins i.e. COM pins of MAX4662 to give an input & Control pins
i.e. IN pins of MAX4662 are connected to NOT gate to control/select data pins one by
one. Only that internal switch will be closed which IN pin has logic high control &
MAX will get input data from that switch. Output is taken from NO pins which will
nothing but the input data of MAX4662.
‘ Pin Description :-
PIN
No.
FUNCTION NAME
1 Logic-Control Digital Inputs IN1
2 Analog Switch Common Terminals COM1
3 Analog Switch Normally Open Terminals NO1
4 Negative Analog Supply-Voltage Input. Connect to
GND for single supply operation.
V-
5 Ground GND
6 Analog Switch Normally Open Terminals NO4
7 Analog Switch Common Terminals COM4
8 Logic-Control Digital Inputs IN4
9 Logic-Control Digital Inputs IN3
10 Analog Switch Common Terminals COM3
11 Analog Switch Normally Open Terminals NO3
12 Logic-Supply Input VL
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13 Positive Analog Supply Input V+
14 Analog Switch Normally Open Terminals NO2
15 Analog Switch Common Terminals COM2
16 Logic-Control Digital Inputs IN2
Table 1 – Pin Description Of MAX4662
2.1.3 NOT Gate :
In digital logic, invert or NOT gate is a logic gate which implements logical
negation. Digital electronics circuits operate at fixed voltage levels corresponding to a
logical 0 or 1 (see binary). An inverter circuit serves as the basic logic gate to swap
between those two voltage levels. Implementation determines the actual voltage, but
common levels include (0, +5V) for TTL circuits.
Here, 74HC04N IC is used as a NOT gate. As per working of the project, FRC
pin will be selected when one of the switches of switching IC will be closed. Switch is
closed only when it gets high logic at its control pin. Decoder used here is active low
& will give low level logic at control pin of switching IC. So, by getting low logic
none of the switches will be closed. To give high logic at control pin, NOT gate is
used. Output of decoder is given to input of NOT gate & it will be inverted. This
inverted output is given to control pin to close a switch. Thus, by using NOT gate
FRC pin can be selected one by one even if using low active decoder.
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Figure 5 – Pin Diagram Of 74HC04N
‘ Pin Description :-
Table 2 – Pin Description Of 74HC04N
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2.1.4 Decoder :
As its name indicates, a decoder is a circuit component that decodes an input
code. Given a binary code of n-bits, a decoder will tell which code is this out of the 2n
possible codes. Thus, a decoder has n- inputs and 2n outputs. Each of the 2n outputs
corresponds to one of the possible 2n input combinations.
The DM74LS154 have 4 binary select inputs (A, B, C, D). If the device is
enabled these inputs determine which one of the 16 normally HIGH outputs will go
LOW. Two active LOW enables (G1 & G2) are provided to ease cascading of
decoders with little or no external logic.
Here, DM74LS154N decoder is used to control MAX4662 IC. But, this
decoder is active low i.e. decoder output pin will at logic low level when
corresponding address code is given to decoder inputs, & MAX IC will switch only
when it will get logic high control. So, I cannot give decoder output directly to control
pins of MAX IC. To invert decoder output NOT Gate is used. So, Decoder output is
sent to input of NOT gate &output of NOT is then given to MAX IC.
Figure 6 – Pin Diagram Of DM74LS154N
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Each pin of decoder has its own address which is nothing but a binary
combination. Output pin is selected by giving binary combination to input pins of
decoder & that selected pin will go at logic low. Selection of output pins is shown in
truth table which is for 74LS154N decoder IC.
‘ Truth Table :-
Table 3 ‘ Truth Table Of DM74LS154N
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2.1.5 PIC Controller :
Here, PIC controller selects output pins of decoder by interfacing decoder
address lines to PIC. A binary address combination is sent to decoder input pins
through PIC. Also, it gets input & output voltages at selected pins of FRC one by one
& measures voltage difference of every pins one by one. The evaluated voltage
difference of FRC pin is compared with desired set value & accordingly test report
will be displayed on PC by interfacing RS-232 module to PIC.
To complete all these tasks I have choose PIC16F877A. A PIC16F877 is 40
pins, 8-bit CMOS Flash MCU with 8 inputs ADC, which provides a highly flexible
and cost effective solution to many embedded control applications.
A PIC microcontroller is a processor with built in memory and RAM and
which can be used to control projects. So, it saves building a circuit that has separate
external RAM, ROM and peripheral chips.
The ADC can be used during sleep but it should be used in the RC clock
mode. One benefit of this is that there will be no digital switching noise so we will get
better conversion accuracy.
It’s much easier to use a high level language such as C for programming in
PIC microcontroller.
‘ FEATURES:
RISC architecture
Only 35 instructions to learn
All single-cycle instructions except branches
Operating frequency 0-20 MHz
Precision internal oscillator
Factory calibrated
Software selectable frequency range of 8MHz to 31KHz
Power supply voltage 2.0-5.5V
Consumption: 220uA (2.0V, 4MHz), 11uA (2.0 V, 32 KHz) 50nA
(stand-by mode)
Power-Saving Sleep Mode
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Brown-out Reset (BOR) with software control option
35 input/output pins
High current source/sink for direct LED drive
software and individually programmable pull-up resistor
Interrupt-on-Change pin
8K ROM memory in FLASH technology
Chip can be reprogrammed up to 100.000 times
In-Circuit Serial Programming Option
Chip can be programmed even embedded in the target device
256 bytes EEPROM memory
Data can be written more than 1.000.000 times
368 bytes RAM memory
A/D converter:
14-channels
10-bit resolution
3 independent timers/counters
Watch-dog timer
Analogue comparator module with
Two analogue comparators
Fixed voltage reference (0.6V)
Programmable on-chip voltage reference
PWM output steering control
Enhanced USART module
Supports RS-485, RS-232 and LIN2.0
Auto-Baud Detect
Master Synchronous Serial Port (MSSP)
supports SPI and I2C mode
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Figure 7 – Pin Diagram Of PIC16F877A
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‘ Pin Description :
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Table 4 ‘ Pin Description Of PIC16F877A
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‘ Basic Circuits Of PIC Controller :
Power Supply Circuitry :-
To start up PIC16F877A, there are 7 pins which should be
connected correctly. Likes others electronic component, the supply pin
is the most important. The ideal voltage for PIC16F877A is 5V (Direct
Current). It should not be higher than 5.5V & should not be less than
2V. Picture below shows how to connect supply circuit to PIC16F877.
Figure 8 – Pin Configuration For Power Supply Circuitry
VCC (+5V) GND
PIN 11 PIN12
PIN32 PIN31
Table 5 ‘ Pin Description For Power Supply Circuitry In PIC
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Reset Circuitry :-
There are 7 pins should be connected in order to operate PIC. 4
pins are already connected which is 2 pins for 5V and 2 pin for ground
(negative). The other important pin is Reset pin (MCLR – Master Clear
Reset at Pin number 1). If PIC read 0V at MCLR pin, it will reset the
program, so if MCLR pin is not connected with 5V, PIC will remain
reset and program will not execute. To use the reset function, it’s
needed to create logic condition which is 1 and 0 to the reset pin. 1
means the reset pin will get 5V. If the reset pin logic is 1, then the
program in PIC will execute, but if the reset pin logic condition is 0
(which is 0V) then PIC will not execute the program. The correct way
to add up a switch in order to create the logic condition is shown in
figure.
Figure 9 – Pin Configuration For Reset Circuitry
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When the switch is not pushed, current will flow trough 10K
resistor and MCLR Pin. As a result, MCLR Pin receives 5V and PIC
read it as logic 1. But when switch is push, current will flow through
10K resistor, switch and directly to ground. There is no voltage will
receive at MCLR Pin. This gives 0 logic at MCLR Pin
.
Oscillator Circuitry :-
Five from seven of important pins are already covered, now
there are only 2 pins left which are pin number 13 and 14. These pins
are named as OSC1 and OSC2 respectively. The crystal oscillator from
various frequency is connected between these pins. Sometimes, pulse
generated from the oscillator will have the noise. To reduce the noise,
two capacitors in Pico farad value are needed. The values of capacitors
are dependent on the speed of oscillator that is used.
Figure 10 – Pin Configuration For Oscillator Circuitry
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2.1.6 RS – 232 Module :
‘ Serial Communication :
Serial communication is a way enables different equipments to
communicate with their outside world. It is called serial because the data bits
will be sent in a serial way over a single line. A personal computer has a serial
port known as communication port or COM Port used to connect a modem for
example or any other device, there could be more than one COM Port in a PC.
Serial ports are controlled by a special chip called UART (Universal
Asynchronous Receiver Transmitter).There are several serial communication
standards like RS-232, SPI, I2C etc. of which RS-232 is a asynchronous
method. That means it does not have a synchronizing clock line. One way data
requires only one conductor line. Since it is a two way communication, there
are two lines between the two devices. One for sending data called the Tx and
one for receiving data called the Rx.
RS-232 based serial communication is used for short range as well as
long range communication (cables length longer than 2 meters). High voltage
input output and requirement of fewer wires makes it ideal for long range
communication.
Figure 11 ‘ Image Of DB-9 COM Port
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‘ Level Conversion :
Here, I am going to generate a full test report of FRC with each pin.
For that PC will be interfaced to PIC Controller by RS-232 module which is
knowingly used for serial communication. At this point we should become
familiar with a point that voltage level on RS-232 line is different from the
voltage levels generally used in microcontrollers and other ICs. So, to
interface RS-232 level signals to our MCUs we need a "Level converter".
Figure 12 – Block Diagram Of level Converter
A level converter will convert RS-232 level signals (HIGH= -12V
LOW= +12V) from PC to TTL level signal (HIGH=+5V LOW=0V) to be fed
to MCU and also the opposite. Usually all the digital ICs work on TTL or
CMOS voltage levels which cannot be used to communicate over RS-232
protocol. So a voltage or level converter is needed which can convert TTL to
RS232 and RS232 to TTL voltage levels. The most commonly used RS-232
level converter is MAX232.
PC
LEVEL
CONVERTER
MCU
RS ‘ 232 IN
RS ‘ 232
TTL OUT
TTL IN
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‘ MAX232 IC :
As RS-232 is such a common protocol there is a dedicated IC designed
for this purpose of "Level Conversion". This IC is MAX232 from Maxim. By
using charge pumps it generates high voltages (+12V) and negative voltages
(-12V).
Figure 13 ‘ Pin Diagram Of MAX-232
‘ Interfacing UART with PIC16F877A :
Here, I want to display the whole test report for FRC pins in PC. To
display a text in PC from PIC16F877A, Evaluation Board by using UART
module is needed. In PIC16F877A Evaluation Board contains a single serial
interface that is UART. The Transmitter pins send the data into PC and the
receiver pin receives the data from PC. The PC and microcontroller speed are
denoted by using baud rate. When the baud rates of both PC and
Microcontroller are same, then only the data transmit and receive correctly
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otherwise not. The TXD (PORTC.6) & RXD (PORTC.7) pins are used to data
transmit or receive operation.
Figure 14 ‘ Pin Configuration Of Interfacing UART With PIC
UART DB-9 Connector PIC Processor Lines
TxD PORTC.6
RxD PORTC.7
Output: Type a character, same character will be returned from board.
Table 6 ‘ Pin Description For Interfacing UART With PIC
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Chapter 3:- Literature Survey
At Hitachi Hi-Rel Power Electronics, IGBT and Thyristors are being used in cards of
UPS which need gate pulse to drive. These pulses are sending through FRC from one card to
another. As time being, any loose contact or partially damaged cable generates a big problem
in passing sensitive signals. This problem cannot be rectified in continuity tester.
The testers available in the market can check only wiring continuity, opens-shorts and
mis-wiring. They compare transmitted and received data between the two ends of the cable
and the result is shown by LEDs.
But this continuity testing is not enough. Drop or distortion in received signal from
FRC can rectify reliability of FRC. Continuity Testers do not consider behavior of
transmitted or received signal from FRCs. So, not only continuity testing is enough but
reliability checking of FRC is also very important & it gives accurate result about FCRCs.
To overcome this limitation of available FRC testers & to solve company’s problem
we have got an innovative idea about this project, which is nothing but to check FRCs
accurately & to generate its full test report with 0 errors which can be shown as a proof.
Components used in the project are commonly used by company in the production of
UPS cards. As described above, MAX-4662 switching IC, 74HC04N-NOT gate,
DM74LS154N-Decoder & MAX-232 are used in CONTROL CARD of UPS. PIC16f877A is
used in CONTROL CARD of UPS in Railway Department.
Thus idea of project comes from the problems faced by company & limitations of
available market solutions.
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Chapter 4:- Implementation Of The Project Work
4.1 System Analysis & Design Of Circuit :
As project name states, here is a tool which test the Flat Ribbon Cable &
generate a full test report with detection of faulty & ok pins. For the sake of
simplicity, this tool is designed for 10 pins FRC.
4.1.1 Basic Principle :
The project is worked on the principle of Ohm’s Law. As stated above, to find
out dropped voltage between two pins we should have input & output voltages of that
path. Now, the input voltage is known but output voltage depends on the resistance of
FRC pin which is unknown here. According to Ohm’s law the value of Reference
Resistor is decided to calculate current to be passed out from FRC pin & output
voltage is obtained. By knowing input & output voltage we can have dropped voltage
of a particular pin of FRC.
4.1.2 Calculation :
First of all to find out dropped voltage we should have input & output voltages
for particular pins of FRC. Now, output voltage is dependent on resistance of FRC pin
which is unknown here. So, reference resistor is used & calculated its value by
choosing current to be passed out & this value of current is chosen such as all the
components used in the circuit can have capacity to drive that amount of current.
MAX4662 IC has current capacity of 200mA. So, 150mA current is to be passed out
from FRC.
According to reference resistance & resistance of a particular path output
voltage is obtained. By calculating difference of input & output voltages we can have
voltage difference of a particular selected path which is nothing but a dropped voltage
at selected FRC pin.
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So, I = 150 mA = 0.150A
‘ Decide value of Reference Resistor :
Rref =
= V1/ I
= 5V/0.150A
‘ Rref = 33
Thus, to calculate value of dropped voltage of FRC pin 33 is taken as
reference resistor.
Figure 15 ‘ Voltage Divider Circuit
‘ Calculation of Voltage Difference :
If V1 = i/p voltage & Rref = 33
Then according to Ohm’s Law, I = V1/ Rref
Now, by applying supply voltage, o/p voltage is obatained.
So, V2 = o/p voltage of FRC pin
Thus, Dropped voltage across FRC pin is given by;
Vd = V1- V2
Vd=?
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Let’s take an example to calculate voltage difference at a particular pin of
FRC, which is shown in figure 15.
V1 = i/p voltage = +5V & Rref = 33
‘ I = V1/Rref = 5/33
‘ I = 0.150A
V2 = o/p voltage = 3.75V
‘ Vd = V1-V2 = (5 – 3.75)V
‘ Vd = 1.25V
So, the value of Dropped Voltage at selected FRC pin is 1.25V.
4.1.3 Component List :
Name Of Components Quantity
MAX4662 Switching IC 3
74HC04N NOT GATE 2
DM74LS154N Decoder 1
PIC16F877A 1
MAX232 IC 1
LM7805 IC 1
LM7812 IC 1
Diode-IN4148 6
Diode-IN4007 10
20MHz Crystal 1
Resistor – 33 1
Resistor-1K 15
Resistor-10K 1
Capacitor-100nF 4
Capacitor-22 pF 2
Capacitor-1000 ??F 2
Capacitor-1 ??F 4
Capacitor-0.1 ??F 1
Transformer 1
Switch 1
COM Port 1
Table 7 ‘ List Of Components
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4.1.4 Circuit Diagram :
Figure 16 ‘ Circuit Diagram
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4.1.5 Interfacing Circuit :
Figure 17 ‘ Interfacing Circuit Diagram
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4.1.6 Working :
The working of the project can be easily explained from the block diagram,
but here the flow of working is totally opposite from the way shown in block diagram.
Block diagram is actually shows the connections of components.
As shown in circuit, one side of Flat Ribbon Cable is given to +5V supply.
Here, 10 pins FRC is used & we want to find out dropped voltage at each & every
pins of it. Actual working is divided in 3 sections :
1. Select a pin of cable.
2. Measure input voltage of a selected pin.
3. Measure output voltage of that pin.
Now, these 3 sections briefly explained as below:
1. Selection of a pin :
MAX 4662 switching IC is used to select pins one by one. To achieve this,
another side of FRC is connected to COM pins of switching IC. Now, to switch the
pins, switching IC requires HIGH logic at its IN pins. This HIGH logic can be fed
from decoder.
Decoder used here is active low. So, output of decoder pin is at LOW logic.
To give HIGH logic at IN pins of switching IC the output of decoder is fed to it after
inverting it. To achieve this, NOT gate is used. Thus, output of decoder is fed to input
of NOT gate to invert it & this inverted output from output pins of NOT gate is fed to
IN pins of MAX. So, if IN1 is at logic 1 then pin connected to COM1 is selected.
i.e.pin1 of FRC.
Now, decoder output lines are selected by applying addresses of them at input
lines one by one. The address of output lines are predefined in truth table of a
particular decoder. One input line is given one bit either 0 or 1 & combination of all
bits at input lines give address of output pins. For ex. To select 3rd pin of decoder
output, bits combinations at input lines are 0010.
Input lines of decoder are fed to the PIC controller to receive address bits. PIC
Controller sends addresses continuously by increasing one bit & accordingly output
pins of decoder will be selected.
Thus, FRC pin selection is ultimately decided by PIC controller.
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2. Measurement of input voltage of selected pin :
Input voltage of selected pin is fed to the Analog Input pin of PIC. Here, one
side of FRC is connected to the supply voltage, which is directly fed to the PIC as an
input voltage & this input voltage is considered only for a selected pin. For an ex. PIC
gives 0010 combination to the input of decoder. So, 3rd output line is selected & gives
0 logic to NOT gate. Then NOT will invert it & will give logic 1 to IN3 pin of
MAX4662. Due to this IN3 pin will have HIGH logic & accordingly connected FRC
pin to COM3 will select. At the instant input voltage of this 3rd pin of FRC is fed to
PIC & stored it.
3. Measurement of output voltage of selected pin :
After sending input voltage to PIC, output voltage is fed to another Analog
Input pin of PIC. This output voltage is measured from corresponding NO pins of
selected FRC pin in switching IC. So, output voltage is sent to PIC with reference to
33?? resister. If IN3 is at logic 1then voltage of FRC pin connected at COM3 is
switched to NO3 pin & output voltage is measured from it via PIC.
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4.2 Hardware Implementation :
Figure 18 ‘ Hardware Implementation
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Figure 19 ‘ Soldering on GPB
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4.3 Algorithm Of Program :
Start
Assign decimal to counts & sore such as,
(5)10=1024 to (0)10=0000 where (2.5)10=512
Initialize the address of decoder pin for
selection in hex.
Convert address into binary & store it.
Initialize counter
Increment the value of address for decoder
pins
Measure an analog input voltage for selected
pin of FRC (here V1)
Convert value of analog input voltage into
digital & store it
Define the register/variable for storage
Measure an analog output voltage for
selected pin of FRC (here V2)
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NO
Convert value of analog output voltage into
digital & store it
Calculate the difference of input & output
voltage for selected pin (here V1-V2=Vd)
Convert Vd into decimal, store it with its
assigned count & name it Vdcount
Compare Vdcount with count of (2.5)10 i.e.
with 512
If 512 > Vdcount
YES
Store bit 1 as a result
Store bit 0 as a
result
Decrement the value of counter
Send request to display value of calculated
resistance
If counter
value is 00h
YES
NO
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If
acknowledgement
is received
Send the Test Report having 0 & 1 results of
10 pin FRC to display on PC
Stop
YES
NO
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4.4 Software & Program :
‘ About Software :
To generate full test report of FRC Hyper Terminal is used here. Hyper
Terminal is a program that can be used to connect other devices. Hyper Terminal
records the messages passed to and from the computer or service on the other hand of
connections. To make sure that device is connected properly, we can send commands
through Hyper Terminal & check the results. Hyper Terminal is designed to be an
easy-to-use tool and is not meant to replace other full-feature tools available on the
market.
‘ Steps To Run Hyper Terminal :
1. Open Hyper Terminal.exe and write a name in connection description.
Figure 20 ‘ Screen Shot 1
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2. Fill details in another opened dialogue box & choose proper COM Port
in Connect Using.
Figure 21 ‘ Screen Shot 2
3. Select proper baud rates same as used in interfacing device.
Figure 22- Screen Shot 3
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4. Apply Flow Control as NONE. Click OK.
Figure 23 ‘ Screen Shot 4
‘ About program :
The program of this project is in C language. C is a general purpose high level,
structured language. Program is written in to text files with extension ‘.c’
The tools required for C programming are :
1. A text Editor : A text editor allows to type in, modify and save program.
Notepad in windows, Edit in DOS are some popular text editors.
2. A C Compiler : A compiler is a program that converts the high-level
language program into machine language. Turbo C, Turbo C++ and
Microsoft C are some of the popular compilers that work under MS-DOS.
Visual C++ and Borland C++ are the compilers that work under Windows.
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Chapter 5:- Result Analysis
The Full Test Report of FRC reliability is generated in Hyper Terminal. Here, an
analysis report of one 10 pin FRC is shown. ‘0’ bits in the report indicate faulty pins & ‘1’
bits indicate ok pins in particular FRC. ‘A’ bit is a starting bit & then rectified output for 10
pins is displayed. After displaying result of 10 pins the bit string will be displayed again with
starting bit ‘A’. Thus, report is generated continuously, until device is disconnected.
Figure 24 ‘ Detailed Report of FRC on Software
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Chapter 6:- How To Troubleshoot
‘ Care that device don’t get damaged physically.
‘ If you find system not working properly then check first power supply, if there is not
enough voltage then check connection and make sure that all ICs get enough voltage.
‘ Even though if it will not work then change crystal voltage at pin XTL1 and XTL2. If
crystal is not working then change it.
‘ If power supply is correct then check PIC controller, get it out from socket and check
from Burner or CRO or logic analyzer that your controller working properly.
‘ If controller is working properly then check connections from controller to RS-232
module if there is any pin which is in open circuit!
‘ Also check data are successfully transmitted & received from controller to MAX232
& from MAX232 to DB-9 connector on CRO by checking data signals.
‘ If all connections to interfaced module are correct and even though it isn’t working
then change PIC IC!
‘ Load program in IC again and turn on the system again.
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Chapter 7:- Conclusion
Advance FRC Checker With Detailed Resistivity Report is a tool which can test the
Flat Ribbon Cables accurately, detects open-shorted wiring and generate full test report with
the detection of faulty/ok pins. Thus, by using this tool, full proof of reliability for each pins
of FRC with 0 error can be generated and CPU will memorize pass/fail testing of numerous
cables. So, each FRC will have its detailed report of its reliability after testing it.
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Chapter 8:- Limitations
‘ This tool is the innovation for company. So, for the sake of simplicity it is
designed only for checking 10 pins FRCs. It can’t check FRCs with more number
of pins or multiple pins.
‘ No. of FRCs is joined one by one to generate a resistivity report with this tool.
Due to frequent connection-disconnection FRC to the connector of a tool, it
creates a loose connection problem & it affects the test result.
‘ The tool is limited to check only one type of cable which is Flat Ribbon Cable. No
other type of cable can be checked.
‘ The FRC Checker is designed for the project purpose. So, the components used
are having limited capacity of voltage & current. Thus, it’s rated with low current
conduction. Due to this reason it’s not applicable to an industrial use.
‘ The test report is generated only by interfacing the tool with PC having Hyper
Terminal Application.
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Chapter 9:- Expansion Scope
‘ This tool can be added to signal testing circuit for using it in multiple purposes.
‘ It is versatile for FRCs with multiple no. of pins.
‘ To overcome problem of loose contact after long term, an FRC connector with
maximum no. of pins can be used in a tool and a test report will be generated by
sensing no. of pins without attaching a cable with a connector.
‘ To use this tool for an industrial application, it can be modified for higher rated
current conduction by using components with higher conduction capacity.
‘ The Test Report can be generated in any other program such as Word, Excel, and
Notepad etc. by adding a Visual Basic application in programming.
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Chapter 10:- References
‘ Reference Books :-
M. Morris Mano : Digital Design Second edition : Eastern Economy
Edition : PHL
R. P. Jain : Modern Digital Electronics, Tata McGraw Hill Publication
Richard Barnett, Larry O’Coull, Sarach Cox : Embeded C
Programming With The Microchip PIC
V K Mehta & Rohit Mehta : Principles Of Electronics, S. Chand
Publication
‘ Websites :-
http://www.electro-tech-online.com
http://www.datasheetdirect.com
http://www.keil.com/appnotes
http://www.datasheetcatalogs.com
www.extremeElectronics.co.in