Telephone Remote System - EECS Senior Design Project

Transcription

Telephone Remote System
Control Your Home Appliances Miles Away
Senior Design Project Documentation
Winter 2007 EECS 129B
Professor Raymond Klefstad
By
Shao-Lin Chen
Mingruey Lee
Sam Lee
ABSTRACT
This documentation is a comprehensive guideline of Telephone Remote System, a home
automation device. It provides information of how to build, test and use the system. The system
consists of two devices; one being the master device and the other being the slave device. The
master device takes commands through DTMF signals from incoming telephone. If the
command is valid, master then issues command to slave device through wireless communication
protocol to turn on/off appliances attached to the slave device.
TABLE OF CONTENTS
Figure 1 – Overview 3....................................................................................................................2
Figure 2 – CM8870 Conversion Table 4.......................................................................................2
Figure 3 – Master front and power 6...........................................................................................2
Figure 4 – Master zigbee and phone jack 6.................................................................................2
Figure 5 – Slave front and power 7..............................................................................................2
Figure 6 – Slave 4 relay outputs 7................................................................................................2
Figure 7 – Slave device on top of master device 7.......................................................................2
Figure 8 – Master device system level diagram 8........................................................................2
Figure 9 – Actual master device circuits 8...................................................................................2
Figure 10 – Slave device system level diagram 9.........................................................................2
Figure 11 – Actual slave device circuits 9....................................................................................2
Figure 12 – Ring Detection Circuit (M1) 10................................................................................3
Figure 13 – Pick Up circuit (M2) 10.............................................................................................3
Figure 14 – DTMF Decoder circuit (M3) 11................................................................................3
Figure 15 – ZigBee Wireless circuit (M4 & S1) 11......................................................................3
Figure 16 – Relay Control circuit (S2) 12....................................................................................3
Figure 17 – Master flow chart 13.................................................................................................3
Figure 18 – Slave float chart 14....................................................................................................3
TABLE OF FIGURES
Figure 1 – Overview.......................................................................................................................4
Figure 2 – CM8870 Conversion Table..........................................................................................5
Figure 3 – Master front and power..............................................................................................6
Figure 4 – Master zigbee and phone jack....................................................................................6
Figure 5 – Slave front and power.................................................................................................7
Figure 6 – Slave 4 relay outputs...................................................................................................7
Figure 7 – Slave device on top of master device..........................................................................7
Figure 8 – Master device system level diagram...........................................................................8
Figure 9 – Actual master device circuits......................................................................................8
Figure 10 – Slave device system level diagram............................................................................9
Figure 11 – Actual slave device circuits.......................................................................................9
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Figure 12 – Ring Detection Circuit (M1)...................................................................................10
Figure 13 – Pick Up circuit (M2)................................................................................................10
Figure 14 – DTMF Decoder circuit (M3)...................................................................................11
Figure 15 – ZigBee Wireless circuit (M4 & S1).........................................................................11
Figure 16 – Relay Control circuit (S2).......................................................................................12
Figure 17 – Master flow chart....................................................................................................13
Figure 18 – Slave float chart.......................................................................................................14
PURPOSE
Our senior design project is inspired by a simple, yet convenient idea of using telephone
as remote control to switch on/off electronic devices. With such intention in mind, we are to
design and implement a dynamic central command unit, which decodes the DFMF signals from
incoming telephone calls, and uses the decoded information to remote control on/off stage of
electronic devices.
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Figure 1 – Overview
FEATURES
 A master device that picks up user’s phone call and allows user to enter commands
wherever and whenever, as long as a phone call is picked up successfully.
 With a valid command, master device can signal slave device to turn on/off up to four
electronic devices.
 The slave device is wireless connected to the master device via ZigBee, which allows a
more versatile positioning of our master and slave devices.
 After hanging up the call, the system is reset and ready for the next incoming call.
BACKGROUND
The most essential part of our system is the audio DTMF decoder (CM8870). Without it,
our design will not be able to detect commands from telephone calls.
First of all, what is a DTMF signal? Dual-tone multi-frequency (DTMF) is a tone signal
used for telephone signaling over the line in the voice-frequency band. The version of DTMF
used for telephone tone dialing is known by the trademarked term “Touch-Tone” and is a
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standardized telecommunication median. As a result, any functional “Touch-Tone” phone should
generate the identical DTMF tones specified for all 12 buttons on a standard touch-tone phone.
The DTMF decoder, as suggested by its name, is used to detect and decode received touch in a
telephone call, i.e. when you press a number button while you are on a phone, you can hear the
sound of the button you press, the DTMF decoder will detect such valid tone and decodes it into
a unique4-bit binary number (Figure 2). This 4-bit binary number will be output to the master,
and the program will verify the sequence of numbers to determine if the input is a valid
command.
KEY
1
2
3
4
5
6
7
8
9
0
*
#
TOW
H
H
H
H
H
H
H
H
H
H
H
H
Q4
0
0
0
0
0
0
0
1
1
1
1
1
Q3
0
0
0
1
1
1
1
0
0
0
0
1
Q2
0
1
1
0
0
1
1
0
0
1
1
0
Q1
1
0
1
0
1
0
1
0
1
0
1
0
Figure 2 – CM8870 Conversion Table
Another important component in the telephone remote control system is ZigBee. ZigBee
uses low-power digital radios based on IEEE 802.15.4 standard for wireless personal area
networks (WPANs), and it allows wireless connection between the master and slave devices. As
a result, slave device can be placed anywhere within the range of ZigBee connection, therefore
create a more user friendly and convenient infrastructure of our system.
SYSTEM CONFIGURATION
The whole system is separated into two devices: master device and slave device, each
with its own power source and indicators.
1.
Master Configuration
The master device contains the circuits to detect and pick up an incoming phone call and
a DTMF decoder to decode commands. In a way, the master device is very similar to an
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answering machine. The master device automatically picks up a phone call after 3 rings. After
the phone is picked up, the user will be able to enter command to the master device. The
commands are to be decoded and send to slave device through ZigBee if valid.
When master device is powered up, the StandBy LED (red) indicates that the device is in
standby mode and is ready to accept any incoming call. When there is an incoming call, the
Ring LED (green) provides feedback on whether or not the phone is ringing. After the call is
picked up, then the Connected LED (green) is on. If the entered command is valid, the Command
LED (yellow) will flash.
Input: 9V power
Output: ZigBee signal
RJ-11 phone jack
Figure 3 – Master front and power
2.
Figure 4 – Master zigbee and phone jack
Slave Configuration
The slave device consists of ZigBee to accept commands. If a command is valid, then the
slave device can turn either device 1, 2, 3, 4 or all on/off using on board circuit to control relays.
When slave device is powered up, the StandBy LED (red) indicates that the device is in
standby mode and is ready to accept any signals from master device. The four LEDs numbered
1, 2, 3 and 4 are used to indicate whether or not the corresponding relays are on.
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Input: 9V power
Output: 4 relay outputs
ZigBee signals
Figure 5 – Slave front and power
Figure 6 – Slave 4 relay outputs
Figure 7 – Slave device on top of master device
SYSTEM LEVEL DIAGRAMS
1.
Master System Level
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Figure 8 – Master device system level diagram
When there is an incoming call, the Ring Detect Module (M1) detects rings and provides
feedback to Arduino. Once 3 rings are detected, Arduino tells Hook on/off Module (M2) answers
the call. Once the call is connected, DTMF Decoder Module (M3) decodes any DTMF signal
from the call. Once a valid input is detected, Arduino sends the action signal to slave device with
ZigBee Module (M4).
Figure 9 – Actual master device circuits
2.
Slave System Level
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Figure 10 – Slave device system level diagram
Once the slave device receives the action signal from the master device, it will respond to
it by turning on/off either device 1, 2, 3, 4 or all. The output devices’ on and off states are
indicated by their own LED lights.
Figure 11 – Actual slave device circuits
CIRCUIT LEVEL DIAGRAMS
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1. Ring Detection Circuit (M1)
Figure 12 – Ring Detection Circuit (M1)
Ring Detect Circuit (M1): When the circuit is in idle state, the voltage between collector
and emitter is 5V. Once the phone rings, the voltage will drop to 3.7V. Measurement of this
voltage change can be used to detect how many rings occur on the phone before the system
activates Switch Hook Module. The LED indicates ringing.
2. Pick Up Circuit (M2)
Figure 13 – Pick Up circuit (M2)
Pick Up Circuit (M2): This module is used to pick up an incoming call. When a phone is
not in use, the voltage across the phone line is 50V; when this voltage drops to around 36V,
the phone picks up. This circuit is used to provide such load to the phone line causing it to
pick up, and is controlled by the Arduino’s digital pin2. By default, pin2 is set to High, and
when it switches to Low, it activates the load circuit, causing the voltage to drop to 36V and
the phone picks up.
3. DTMF Decoder Circuit (M3)
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Figure 14 – DTMF Decoder circuit (M3)
DTMF Decoder Circuit (M3): This circuit contains an essential chip for our project. The
CM8870 chip is capable of decoding analog DTMF signal into binary signal for numeric
recognition. The output of this chip is the combination of Q1 – Q4, and the combination can
be defined by the Arduino program to indicate numbers for the corresponding phone keys.
4. ZigBee Wireless Circuit (M4 & S1)
Figure 15 – ZigBee Wireless circuit (M4 & S1)
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ZigBee Wireless Circuit (M4 & S1): This module is adapted from one of 129A lab
assignment last quarter, and is a very convenient component for wireless data transmission.
By adding ZigBee Module to both our master and slave device, the two can communicate
with each other in wireless connection, which improves the versatility of our project.
5. Relay Control Circuit (S2)
Figure 16 – Relay Control circuit (S2)
Relay Control Circuit (S2): This component basically reacts to the input from the master
device and switch on the appliances that are connected to it. By default, all relays are open
and the appliances are turned off. By responding to the input, the relay will close the switch
to turn on the connected appliances.
SOFTWARE DESCRIPTION
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1. Master Software
Figure 17 – Master flow chart
The software of master device follows the above simple flow chart. When the power is
on, the device is in Ready stage. Whenever there is an incoming call, the device picks up and
enters Pick Up stage. During Pick Up stage, the device is ready for decoding commands. If the
command is valid, a signal is send to slave device. Otherwise, it will go back to Pick Up stage.
If user hangs up the call, the device will go back to Ready stage.
The full source code of master device is included in Appendix A in page 19.
2. Slave Software
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Figure 18 – Slave float chart
The software of slave device follows the above simple flow chart. When the power is on,
the device is in Ready stage. Whenever there is a valid signal from Zigbee, the slave turns on
/off either device 1, 2, 3, 4, or all. After performing an action, the slave device goes back to
Ready stage.
The full source code of master device is included in Appendix B in page 24.
TESTING PLAN
1. System test plan:
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1. Plug in power for both master and slave devices.
2. Connect the master device to a working phone jack. It is preferable using a splitter to
connect a working phone with it.
3. Call the number of that phone.
4. After 3 rings, the master device will pick up the call.
5. When the call is connected, one can enter command from his or her touchtone phone pad.
6. Dial 10 to turn on, 11 to turn off slave device 1.
10. Dial 00 to turn on, 01 to turn off slave device 1, 2, 3 and 4.
11. Dial any other numbers will result in an invalid command.
12. Dial ## to tell the master device to hang up the phone.
13. If no key is pressed, the master should hang up by itself after 35 seconds of idling.
2. Individual module testing:
Master:
1. Ring Detect Circuit (M1): Connect this module to a working phone jack. Measure the
voltage between the collector node and emitter node. This module is function properly if
we can see the voltage drop from 5V to 3.7V each time a ring occurs.
2. Pick Up Circuit (M2): Connect this module to a working phone jack. Short pin2 of
LCA110 and call the number. If the phone is picked up automatically then this device is
functioning correctly.
3. DTMF Decoder Circuit (M3): Connect this module to a working phone jack and to the
Arduino board. When a phone call is picked up, test the decoder by pressing each number
key as well as the # and * key to see if the input is decoded correctly.
4. ZigBee wireless Circuit (M4): To test ZigBee’s wireless connection, we must configure
the master Arduino to send test signal through it to the slave Arduino. If a signal is sent
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and successfully received by the slave Zigbee, the signal should be read by the slave
Arduino and output on the PC programmer.
Slave:
1. ZigBee wireless Circuit (S1): This can be tested together with the master Zigbee module.
2. Relay Control Circuit (S2): Use Arduino digital pin2 to pin5 to send the device control
signals to the relays. If the signals are High, relays will switch from NC to NO, and the
circuits are connected, indicating by the LED lights. Once the signal becomes Low, the
relays will switch back to NC, and the circuits are disconnected.
COST ANALYSIS
MASTER
Resistors 1/4W Carbon Film
56
100
Quantity
1
1
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Total Price
$0.05
$0.05
Part Number
56-1/4
100-1/4
Vendor
All Electronics
All Electronics
Page 16
820
2.2k
10k
22k
47k
100k
300k
Capacitors
.1uf ceramic
10nf metallized polyester
120nf metallized polyester
330nf polyester film
1uf electrolytic
4.7uf electrolytic
IC Chips
CM8870 (DTMF decoder)
4N25
LCA110
74HC245
74LVC245
Zigbee
crystal oscillator 3.5795mHz
Semiconductor
W02M (bridge rectifier)
MPSA42
MJE340
1N4004 (diode)
Others
150LA10 (MOV)
phone jack RJ-11
power regulator 5V-3.3V
Coupling transformer 600:600
LED
Programmer
Arduino USB Atmega8
1
1
2
1
4
2
1
$0.05
$0.05
$0.10
$0.05
$0.20
$0.10
$0.05
820-1/4
2.2K-1/4
10K-1/4
22K-1/4
47K-1/4
100K-1/4
300K-1/4
All Electronics
All Electronics
All Electronics
All Electronics
All Electronics
All Electronics
All Electronics
2
2
1
1
2
1
$0.16
$0.34
$0.22
$0.40
$1.00
$0.50
1109PHCT-ND
495-1097-ND
478-2250-ND
BC1782-ND
4062PHCT-ND
4065PHCT-ND
Digi-Key
Digi-Key
Digi-Key
Digi-Key
Digi-Key
Digi-Key
1
1
1
1
1
1
1
$1.30
$0.50
$2.30
$0.58
$0.60
$23.20
$3.00
M-8870-01-ND
4N25MFS-ND
CLA101-ND
568-1423-5-ND
296-8503-5-ND
XB24-AWI-001-ND
300-7007-1-ND
Digi-Key
Digi-Key
Digi-Key
Digi-Key
Digi-Key
Digi-Key
Digi-Key
1
1
1
1
$0.61
$0.29
$0.72
$0.26
W02G/1GI-ND
MPSA42FS-ND
497-2624-5-ND
1N4004DICT-ND
Digi-Key
Digi-Key
Digi-Key
Digi-Key
1
1
1
1
4
$0.22
$0.65
$0.77
$1.00
$0.60
150LA10
MT-64
497-1491-5-ND
TCX-2
LED-2
Digi-Key
All Electronics
Digi-Key
All Electronics
All Electronics
1
$31.95
Arduino-USB
Sparkfun
Sum of Master
1
$71.27
Quantity
7
1
Total Price
$0.35
$0.05
Part Number
1K-1/4
10K-1/4
Vendor
All Electronics
All Electronics
1
1
1
$0.58
$0.60
$23.20
568-1423-5-ND
296-8503-5-ND
XB24-AWI-001-ND
Digi-Key
Digi-Key
Digi-Key
SLAVE
Resistors 0.25W Carbon Film
1k
10k
IC Chips
74HC245
74LVC245
Zigbee
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ULN2003A
Others
relay
LED
Programmer
Arduino USB Atmega168
1
$0.95
97-2344-5-ND
Digi-Key
4
5
$6.52
$0.75
PB892-ND
LED-2
Digi-Key
All Electronics
1
$31.95
Arduino-USB
Sparkfun
Sum of Slave
1
$64.95
Master + Slave Sum
1
$136.82
SUMMARY
Overall we accomplished our project with success and gained a lot of experiences in
circuit design as well as telecommunication technology. In the beginning, we had no prior
knowledge of how telephone worked. It was through an extensive research and study before we
understood the concept behind it and to begin the schematic design, purchasing parts and
actually implementing the circuits. Throughout the project development process, we encountered
one technical issue. The first issue was to connect an auto reset circuit to our master device. The
circuit was designed to detect the voltage change when users hanged up the call and used it to
reset the master device. However, when we implemented the circuit into the master device, it
somehow altered the standby voltage of the phone line, causing it to pick up even without any
incoming call. Worse, the circuit redirected currents into the Arduino board, causing it to
constantly overheat and finally broke the Arduino board. In the end, we abandoned the idea and
programmed the microcontroller using software reset to solve this issue. Nevertheless, the
development process was smooth and we accomplished most of our goal, that our system could
pick up a phone call and allow the caller to control up to four different appliances with few
touches on the keypad, which was pretty interesting experience when we tested it.
APPENDIX A – Master Software Source Code
//--------PIN DECLARE---------//
int ringDetectPin = 0;
int q1 = 1;
int q2 = 2;
int q3 = 3;
int q4 = 4;
int TOW = 5;
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int hook = 2;
int redled = 3;
int greenled = 4;
int yellowed = 5;
////////////////////////////////
//---------VARIABLES----------//
int ringDetectVal = 0;
int q1val = 0;
int q2val = 0;
int q3val = 0;
int q4val = 0;
int TOWval = 0;
int key = 0;
int ringConstant = 0;
int timeStamp = 100000;
int hangUpVal = 0;
int command = 0;
int commandLength = 2;
////////////////////////////////
void setup()
{
Serial.begin(9600);
pinMode(greenled, OUTPUT);
pinMode(redled, OUTPUT);
pinMode(yellowled, OUTPUT);
pinMode(hook, OUTPUT);
digitalWrite(hook, HIGH);
Serial.print("+++");
delay(1100);
//hook is set to off (hangs up)
//Zigbee setup begins
if (returnedOK() == 'T'){}
else{
setup();}
Serial.println("ATID1234,CN");
else{
setup();}
digitalWrite(greenled, LOW);
digitalWrite(yellowled, LOW);
digitalWrite(redled, HIGH);
void loop()
{
ringDetectVal = 1024 - analogRead(ringDetectPin);
if (ringDetectVal > 100)
{
ringConstant = ringConstant + 1;
}
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//Detect ring
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while (ringDetectVal > 100)
//Wait here until next ring
{
ringDetectVal = 1024 - analogRead(ringDetectPin);
}
if (ringConstant > 117)
//If rings for 3 times, picks up the phone
{
pickUp();
digitalWrite(greenled, LOW);
digitalWrite(hook, HIGH);
ringConstant = 0;
}
}
//-----------PICKUP-----------//
void pickUp()
{
digitalWrite(greenled, HIGH);
digitalWrite(redled, LOW);
digitalWrite(hook, LOW);
hangUpVal = 1;
//hangUpVal = 0 will hangs up the phone
while(hangUpVal == 1)
{
TOWval = getDigital(analogRead(TOW));
if (TOWval == 1)
//Read TOW, if TOW=1, a tone is detected
{
timeStamp = 100000;
//
q1val
q2val
q3val
q4val
=
=
=
=
getDigital(analogRead(q1));
key = q1val + 2 * q2val + 4 * q3val + 8 * q4val;
if (key
key =
if (key
key =
== 11)
13;
== 10)
0;
command = command * 10;
command = command + key;
commandLength = commandLength - 1;
if (commandLength == 0)
//A command is entered
{
if (command == 10)
{
Serial.println("10");
digitalWrite(yellowled, HIGH);
delay(200);
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}
else if (command == 11)
{
digitalWrite(yellowled,
delay(200);
}
{
delay(200);
}
{
delay(200);
}
{
delay(200);
}
{
delay(200);
}
{
delay(200);
}
{
delay(200);
}
{
delay(200);
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HIGH);
LOW);
HIGH);
LOW);
HIGH);
LOW);
HIGH);
LOW);
HIGH);
LOW);
HIGH);
LOW);
HIGH);
LOW);
HIGH);
LOW);
Page 21
}
{
digitalWrite(yellowled, HIGH);
delay(200);
}
//command = ##
{
hangUpVal = 0;
}
else
//command is invalid
{
delay(200);
digitalWrite(redled, LOW);
}
}
}
commandLength = 2;
command = 0;
while (TOWval == 1)
//Wait here until next dialing tone
{
TOWval = getDigital(analogRead(TOW));
}
timeStamp = timeStamp - 1;
if (timeStamp == 0)
//If idle for more than 35 seconds, hangs up
{
timeStamp = 100000;
hangUpVal = 0;
}
}
}
////////////////////////////////
//--------AtoDConvert---------//
int getDigital(int analog)
{
if (analog > 1000)
return 1;
else
return 0;
}
////////////////////////////////
//--------ZigBee helper--------//
char returnedOK () {
// this function checks the response on the serial port to see if it was
an "OK" or not
char incomingChar[3];
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char okString[] = "OK";
char result = 'n';
int startTime = millis();
while (millis() - startTime < 2000 && result == 'n') { // use a timeout
of 10 seconds
if (Serial.available() > 1) {
// read three incoming bytes which should be "O", "K", and a linefeed:
for (int i=0; i<3; i++) {
incomingChar[i] = Serial.read();
}
if ( strstr(incomingChar, okString) != NULL ) { // check to see if the
respose is "OK"
//if (incomingChar[0] == 'O' && incomingChar[1] == 'K') { // check to
see if the first two characters are "OK"
result = 'T'; // return T if "OK" was the response
}
else {
result = 'F'; // otherwise return F
}
}
}
return result;
}
////////////////////////////////
APPENDIX B – Slave Software Source Code
//---------Pin Declare--------//
int ledPin = 13;
int device1 = 5;
int device2 = 4;
int device3 = 3;
int device4 = 2;
int led1 = 6;
int led2 = 7;
int led3 = 8;
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int led4 = 9;
////////////////////////////////
//----------Variables---------//
byte inByte = 0;
byte names[] ={'0', '1', '2', '3', '4', '5', '6', '7'};
int tones[] = {0, 1, 2, 3, 4, 5, 6, 7};
int val = 0;
int count = 0;
int command = 0;
////////////////////////////////
void setup()
{
pinMode(ledPin, OUTPUT);
pinMode(device1, OUTPUT);
pinMode(led1,
pinMode(led2,
pinMode(led3,
pinMode(led4,
OUTPUT);
OUTPUT);
OUTPUT);
OUTPUT);
digitalWrite(device1,
digitalWrite(led1,
digitalWrite(led2,
digitalWrite(led3,
digitalWrite(led4,
LOW);
LOW);
LOW);
LOW);
LOW);
LOW);
LOW);
LOW);
Serial.begin(9600);
Serial.print("+++");
delay(1100);
//ZigBee setup
else{
setup();}
Serial.println("ATID1234,CN");
else{
setup();}
digitalWrite(ledPin, HIGH);
//Device is ready
}
void loop()
{
if (Serial.available() > 1)
{
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inByte = Serial.read();
int end = inByte;
if (end != 13)
//End of line is not met
{
for (count=0;count<=8;count++)
{
if (names[count] == inByte)
{
command = command * 10;
command = command + tones[count];
}
}
}
else
{
if (command == 11)
{
digitalWrite(device1, HIGH);
digitalWrite(led1, HIGH);
}
{
digitalWrite(device1, LOW);
digitalWrite(led1, LOW);
}
{
}
{
}
{
}
{
}
{
}
{
}
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{
digitalWrite(led1,
digitalWrite(led2,
digitalWrite(led3,
digitalWrite(led4,
HIGH);
HIGH);
HIGH);
HIGH);
}
{
digitalWrite(led1,
digitalWrite(led2,
digitalWrite(led3,
digitalWrite(led4,
}
}
}
command = 0;
HIGH);
HIGH);
HIGH);
HIGH);
LOW);
LOW);
LOW);
LOW);
LOW);
LOW);
LOW);
LOW);
}
//--------ZigBee helper--------//
char returnedOK () {
// this function checks the response on the serial port to see if it was
an "OK" or not
char incomingChar[3];
char okString[] = "OK";
char result = 'n';
int startTime = millis();
while (millis() - startTime < 2000 && result == 'n') { // use a timeout
of 10 seconds
if (Serial.available() > 1) {
// read three incoming bytes which should be "O", "K", and a linefeed:
for (int i=0; i<3; i++) {
incomingChar[i] = Serial.read();
}
if ( strstr(incomingChar, okString) != NULL ) { // check to see if the
respose is "OK"
//if (incomingChar[0] == 'O' && incomingChar[1] == 'K') { // check to
see if the first two characters are "OK"
result = 'T'; // return T if "OK" was the response
}
else {
result = 'F'; // otherwise return F
}
}
}
return result;
EECS129B
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}
////////////////////////////////
EECS129B
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APPENDIX C – Full Size Diagrams
EECS129B
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Master
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Slave
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Telephone Remote System - EECS Senior Design Project

Transcription

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