Mce Trackme User Eng

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MCE TrackMe (GPS) 2013

MCE TrackMe (GPS) - mcelectronics.com.ar 2012

Tracking system, telemetry and remote controlthrough cellular network.

electronicsmc


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We are a team of professionals that work with passion so as to ensure that our clients

have always a innovative product. We take care of all the details involved in the

fabrication of all our tools. All of our products are designed and assembled in Argentina.

This product counts with 1 year warranty.

More products at:

http://www.mcelectronics.com.ar/desarrollos

Alejandro Airoldi

Responsable for Quality Control

Quality Assurance



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Introduction


TrackMe (GPS) is a telemetry system and remote control through cellular network. It

possesses a GPS and a GSM module. It can transmit through GSM or GPRS, plus it counts

with acceleration, light and temperature sensors. The battery is charged via USB and it

has the possibility to store the coordinates in the internal memory of the PIC18F26J50microcontroller.

TrackMe (GPS) 2013 includes complete projects programmed in CCS. Plus, examples to

decode the GPS NMEA frames, receive commands trough

text messages , use the accelerometer and present the information on

a map using GoogleMaps !


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Layout version 2013


(+) Size comparison

with a cellular phone.

54 mm

85mm


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Components Distribution


Connector for

SIM Card

USB for battery charge and

data transfer.

Charge

indicator LED

GPS Antenna

GSM Antenna

(removable)

Power

indicator LED

Expansion

Header

Panic push

button


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Expansion Header


SIM908

Module

SPEAKER P

SPEAKER N

MIC P

MIC N

BAT

BAT

+3V3

+3V3GND

GND

XOUT

YOUT

ZOUT

IO5

IO4

IO3

IO2

IO1

GSM TX

GSM RX

RING

GSM STATUS

GSM NET

GSM ON

GPS TX

GPS RX+3V3

PANIC

LDR

TEMP

NC

PGD

PGC

GND

+3V3

MCLR

PICKit 2,

PICKit 3 or

another

compatible

programmer


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Switches and LEDs


NET

READY

Flashes every 2sec

when the device

registers to the

cellular network

(must have an active

chip).

It lights up when

the SIM908

module is ready

to operate.

The RF switch can power

on/off the SIM908 module

while the rest of the board is

still working.

RF

MAIN

ON


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Microchip Analog Devices


TC1262-3.3

ANALOG

Charger for

Li-ion

batteries of

each cell.Includes

current

censing and

protection

against

inverse

discharge.

TC1047

3.3v

3.3v

Analog temperature sensor

10mV/C

VBATVIN

MCP73838

VBAT

PIC

18F26J50


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Accelerometer


NC

AN2 X OUT

AN3 Y OUT

AN4 Z OUT

GND

3.3V

NC

NC

NC

NC

NC

NC

NC

3.3V

Freescale MMA7368L

It includes a 3 axis analog accelerometer (X OUT, Y OUT, Z OUT). They are connected

directly to the PIC analog channels.

1.5g Three Axis Low-g Micromachined Accelerometer

PIC Analog

channels

Change rate: 800mV/G

Z

Y

X


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Accelerometer


NC

X OUT

Y OUT

Z OUT

GND

3.3V

NC

NC

NC

NC

NC

NC

NC

3.3V

Freescale MMA7368L


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SIM908 GSM Module


GSM

SIM908

Quad-band : GSM850, EGSM900,

DCS1800, PCS1900

GPRS multi-slot : Class 10 / Class 8

Noise Suppression

Echo Cancelation

Sleep mode current consumption:

1.5mA


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GSM Module Connections


SIM CARD

RFIN

ANT

PIC 18F26J50

SIM TX

SIM RX

GSM

SIM908

SIM BUS

1,8 - 3v

PWRKEY

NETSTATUS

The SIM908 module connects to the PIC through SIM TX (RP0) and SIM RX (RP1) pins. It

also needs the antenna connector and SIM Card to operate.


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SIM908 GSM Module


The SIM908 module needs a 0 on the PWRKEY pin to start. In this case the board has a

common emitter transistor (inverter), for which we must switch the PIC RC1 pin (GSMON)

to 1 to turn on the module.

PWRKEY

Low > 1s. Delay > 2s.

STATUS

The module will automatically shut down (STATUS = low) when supply

voltage is detected outside the 3.3 < VBAT < 4.6 range or when the

temperature is over 85C.

However 0.1v under the limits it sends warnings through the USART.


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AT Commands


The GSM Module is controlled via commands through the USART.

These commands are denominated AT commands.

The AT commands allows you to make phone calls, text messages, consult the module

parameters, measure the cellular signal and set all the SIM900 configurations.

Conversation type communication. The answer must be received before the next

command is sent.

AT (Attention)


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Synchronization


By default it is autobauding enabled. To synchronize the PIC speed with the SIM908 an

A must be sent and up to 3 to 5 seconds must be waited. Then we send the AT

command before initiating communication Once synchronized the SIM900 responds

OK

ATGSM

SIM908PIC

18F26J50

Autobauding Range: 1200 bps to 115200 bps (N,8,1)

A

OK


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Basic Commands


ATI

SIMCOM_Ltd

SIMCOM_SIM900

Revision:1008B10SIM900S32_(SPANSION)SIMCOM_Ltd

AT+GSN // IMEI number from the SIM900

355117001566879

OK

AT+CSQ // Signal level [rssi,ber]

rssi (0= -113dBm o 1= -111dBm o 2 a 30= -109dBm a -53dBm o 31= -51dBmo >/99 no se conoce). ber (% bit error rate)

[17,0]

These commands can be sent through the HyperTerminal (using the USB-GSM driver

included) or through the microcontroller without using the PC.


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Basic Commands


ATD51065802; Make a phone call - SIM908 dials 51065802

AT+CLIP=1 // Show the number of the incoming call (Caller ID)

OK

RING

+CLIP: 51065802",129 // Incoming call number 51065802

OK

ATH // Hang up

RING

ATA // Attend incoming call

OK


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Send a SMS


Sending of the SMS to 51065802

AT+CMGF=1 // Selecting of text mode

AT+CMGS=51065802 // Phone number and 0x0D

> YOUR MESSAGE // Write the message and 0x1A

Returns the position in the memory of sent

OK+CMGS: 123


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Recieve an SMS


Reception of SMS

AT+CMGF=1 // text modeAT+CNMI=2,2,0,0,0 // doesnt save in memory, it sends it through

USART

When a message comes it sends it through TX automatically !

+CMT: 12345678,,28/05/10,11:20:28+32

Hello World


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SIM908 GPS Module


GPS Receiver bases on the 42

channels SIRFstarIII

Consumption less than 77 mA

NMEA protocols or SiRF

Rapid Acquisition of satellites

30 s.

Tracking Sensibility :

-160dBm

GPS

SIM908


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GPS Module Conections


VANT

VRF = 2.85v

RFIN

PIC 18F26J50

GPS TX

GPS RX (*)

GPS

SIM908

ON

ANT LNA

The GPS Module connects to the PIC through the GPS TX (RP3) and GPS RX (RP4) pins. It

needs the antenna and the LNA (Low Noise Amplifier) to operate.

(*) GPS RX is used to request other

frames or vary the reception

interval from the PIC.


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NMEA Frame


NMEA 0183 is a protocol through which the navigational and terrestrial instruments can

communicate. Its been defined, and controlled, by the National Marine Electronics

Association.

In the NMEA frame we have information such as position, velocity, movement direction,UTC hour, satellite position, intensity of incoming and data control.


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Basic NMEA frame


The $GPRMC frame includes basic tracking information and its the one were going to

use to determine the position and other data as velocity, direction and hour.

RecommendedMinimum

Message

UTC Hour

04:03:02.663 AM

$GPRMC,040302.663, A,3939.7, N,10506.6,W, 0.27, 358.86,200812,*1A

A = Active (at least 3 satellites), V = InvalidA

N = North, S = SouthN

W = West, E = EastW

Latitude 3939.7'

Longitude 10506.6'

Velocity meassured in Knots

1 knots = 1.85200 kilometers

Movement direction

(azimuth) 358.86

Date 20/08/12

Checksum*1A

Program to decode the NMEA


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frame


TrackMe GPS includes a program (SirfDemo) to decode the NMEA frame and show

information graphically. We must open the HyperTerminal and select GPS mode (option

2), then we open the SirfDemo software at 4800 bps and click Connect to visualize the

information in real time.



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frame


At least 3 satellites are required to determine the position. In this case all the satellites

are in red which means that there still isnt enough signal.

The GPS must have a clear view to the sky so as to work properly.


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Examples and Applications


All the examples are programmed in C for the CCS compiler. The complete code can be

found along with the board files. Next well describe the basic rutines.

The shaded represents code lines.


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void inicializacionSIM900(void)

{ int cont;

delay_ms(1000);

puts("A",SERIAL_GSM); //to synchronize the SIM900 baudrate

delay_ms(300);

putchar(0x0d,SERIAL_GSM);

delay_ms(3000);

for(cont=0;cont


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#define X_ADC 2 // Define the analog channel

#define Y_ADC 3

#define Z_ADC 4

#define TEMP_ADC 11

set_adc_channel(X_ADC); // Select the channel sith the multiplexor

delay_ms(3); // Define a delay of 3 ms to charge the lecture capacitor

eje_x=read_adc(); // Save the value in the variable

set_adc_channel(Y_ADC);

delay_ms(3);

eje_y=read_adc();

set_adc_channel(Z_ADC);

delay_ms(3);

eje_z=read_adc();

set_adc_channel(TEMP_ADC);

delay_ms(3);

temperature=read_adc();

Read analog channels

In this example the analog channels of the accelerometer and temperature sensor are

selected and the values are stored in variables (definition isnt showed in the box)

l d l


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sprintf(string_temp,"Temp=%1.2f C ",grados);

fprintf(SERIAL_GSM,"AT+CMGS=\"1512345678\"\r"); // put here the cell phone number that receives the SMS

delay_ms(200);

fputs(string_temp,SERIAL_GSM);

delay_ms(100);

fprintf(SERIAL_GSM,"%c",0x1a);

output_high(led);

while(input(PANIC)==0);

Send the temperature through SMS

The complete example consists in reading the TC1047 sensor, convert the tension value

to degrees and send it through SMS when the panic button is pressed. In this fragment

we see that data must be passed as string, for which we convert the degrees variablefrom float to string with sprintf. The same applies when sending the measures of the

accelerometer.

E l d A li i


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if ( kbhit (SERIAL2) ) // Waiting for new data in USART2

{

e=0;

e=getchar(SERIAL2); //Characters are stored in variable e

switch(e)

{

case 10: // Waiting for new line feed

if(cbuffGPS[0]=='$' && cbuffGPS[1]=='G' && cbuffGPS[2]=='P' && cbuffGPS[3]=='R' && cbuffGPS[4]=='M' &&cbuffGPS[5]=='C' && cbuffGPS[18]=='A' ) //Validates if the data is valid (detect at least 3 satellites)

{

PIN_ON(LED);

strcpy(cbuffGPS2,cbuffGPS); // The complete $GPRMC frame is stored in cbuffGPS2

}

xbuff=0;

flag=0;

break;default:

cbuffGPS[xbuff++]=e;

if(xbuff>(lenbuffGPS-1))

xbuff=lenbuffGPS;

}}

Read and save GPS NMEA frame

The idea is to read and save a valid frame in a variable, so as to process it later and send

it as a GoogleMaps link.

E l d A li ti


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if(cbuffGPS2[0]=='$' && cbuffGPS2[1]=='G' && cbuffGPS2[2]=='P' && cbuffGPS2[3]=='R' && cbuffGPS2[4]=='M' &&

cbuffGPS2[5]=='C')

{

strncpy(latg,&cbuffGPS[20],2); // convert to googlemaps coordinatesstrncpy(latm,&cbuffGPS[22],7);

strncpy(longg,&cbuffGPS[32],3);

strncpy(longm,&cbuffGPS[35],7);

latitudgoogle=(atof(latm))/60;

longitudgoogle=(atof(longm)/60);

sprintf(&latitud[1],"%.6f",latitudgoogle);latitud[0]=latg[0];

latitud[1]=latg[1];

sprintf(&longitud[2],"%.6f",longitudgoogle);

longitud[0]=longg[0];



}

Convert to GoogleMaps format

We must obtain latitude and longitude from the $GPRMC frame (cbuffGPS2), plus

convert the values to decimal coordinates. Later they are stored in latitude and

longitude variables.

E l d A li ti


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fprintf(SERIAL_GSM,"AT+CMGS=\"1512345678\"\r"); // put here the cell phone number that receives the SMS

delay_ms(200);

printf("http://maps.google.com/maps?q=-%s,+-%s+(TrackMe esta aqui)",latitude,longitude);

delay_ms(100);

fprintf(SERIAL_GSM,"%c",0x1a);output_high(led);

while(input(PANIC)==0);

Sending a GoogleMaps compatible link

All we have to do is include the latitude and longitude variables, with the appropriate

format, inside the GoogleMaps URL.

User receives a SMS with a

link that shows the location of the board.

E l d A li ti


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Sending data through GPRS

We can send the information to GoogleEarth in real time through GPRS. The trick

consists in sending the complete NMEA frame (without processing) to a TCP server.

Then in the server, which can be our computer, we run an application that allows us tore transfer the received data through TCP to a Virtual COM Port. Finally we open

GoogleEath and select that virtual port as data entry.

This way we can see in real time the position and speed of the board in a GoogleEarth

map.



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Storing data in the PIC internal memory

Its also possible to store the complete frame in the PIC18F26J50 program memory and

then convert this information to KML in the PC to open it with GoogleEarth or

GoogleMaps.

Loading the PIC firmware


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To load a new program to the PIC18F26J50, first we must conect the programmer to

the 6 programming pins, open the program for the PICKit2 and select File->Import

HEX

The manufacture file is mce_trackme_2012.hex and it can be found inside the server

Firmware folder. Then we click Write and the legend Programacin exitosa must

appear concluded the verification.



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Its possible to change the register CONFIG settings without the need of recompiling

the project, clicking on Configuration.

The connecting and programming procedure is identical for the PIC18F26J50.

Its also possible to use MPLAB in case of possessing a PICKIT 3 or ICD3.


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mcelectronics

Buenos Aires - Argentina

Septiembre 2012

MCE TrackMe (GPS)

Manual REV: 09042012

Austria 1760 - OF 8

Ciudad de Buenos Aires (1425).

BA. Argentina.

(011) 3531-4668

www.mcelectronics.com.ar

[email protected]

www.mcelectronics.com.ar

http://www.mcelectronics.com.ar/http://www.mcelectronics.com.ar/

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Mce Trackme User Eng