GSM 1308 MODEM CONTROL USING PIC-16F877A MICROCONTROLLER

GSM 1308 MODEM CONTROL

USING

PIC-16F877A MICROCONTROLLER

Presented by

Supervised By

Dr. A.K.M Fazlul Haque

Associate Professor

Department of ETE

Daffodil International

University

Sk.Mustafizur RahmanID: 082-19-930

Md. Moktarul Islam

ID: 082-19-938

Md.Emam-ul-Uddin

ID: 082-19-939

Aim of the Project:

Controlling the GSM 1308 modem using PIC16F877A by

improving the existing flowcode microcontroller program that

the modem can work as a more general mobile phone.

Content PIC16F877A Microcontroller

E-Blocks

GSM ModemCompiling Procedure

Flowcode Software

Main Programs

Result

Conclusion

PIC16F877A Microcontroller

The name PIC refers to a group of microcontrollers

This is a flexible 40 pin device. The

operating voltage of the microcontroller is

5V

Memory of 16F877A

Flash or EPROM: It is the memory where

the written program is stored.

RAM: It is the memory where the declared

'variables are stored.

EEPROM: It is the memory where the

variables can be permanently stored.

I/O Ports of 16F877A

PORT A : It is connected with Multiprogrammer

board

PORT C: It is Connected with RS232

Communicator

PORT D : It is connected with Keypad

PORT B: It is connected with LCD

E-blocks are small circuit boards each of which consists of a block of electronics that can be snapped

together to form an electronic system. There are two kinds of E-block

E-block

Upstream boards

Downstream boards

Used Components of E-Blocks

EB005 LCD board

EB014 Keypad RS232

Jumper Setting of E-Blocks

Board PORTSettings

Keypad D No settings

LCD B Jumpers on DEFAULT

Sensor A Jumpers on DEFAULT

RS232 CC

Jumpers:

R& TX SELECTION

CTS & RTS SELECTION

1

Patch System wire links:

SPI/DAC CJumpers:

SDO, SDI & SCK SELECTION

A HIP EN SELECTION

1

Patch System wire links:

None

C

Setting up the GSM modem

It can operates between 6vdc to 40vdc

RS232 is used to connect the modem with E-Blocks.

Need a active SIM card with sufficient credit.

Need to connect an Antenna with it to get network connection.

Testing GSM Modem

Before using the GSM modem with E-Block system it needs to be test by

HyperTerminal using different AT Command

•AT+CREG?

•AT%CGREG?

•ATD

•ATH

Checking of GSM, GPRS Setting, Outgoing & Incoming Call

Compiling ProcedureRunning the simulation

Project Software

To complete this project there are two software has been used. Their names are given below:

•Flowcode

•PPP

Steps of Flowcode

Clock setting of Microcontroller

•Crystal clock

•RC clock

Clock signal control the speed of operation.

Selection and Editing of Components

RS232 setting

RS232 is the communicator, which Tx and Rx data modem and PIC micro.

Call Macro icon properties

Call to another Macro. Macro means small programs which used many

time.

Call Component Macro

loop icon properties

Loop while:1 means loop forever.

Loop until: until the condition is true.

Loop count: How many time loop are running.

Decision properties

Calculation icon properties

Provide the logical function

String Manipulation

AT+CREG

AT%CGREG?

AT+CLIP=1,1 to see caller ID

ATD

ATA

ATH

Delay

Programmed is running too fast, So Add the delay function

Open the HEX file Send the program

:020000001C2DB5

:08000800FF00030EFC000A0ECC

:0C001000FD00040EFE008A110A12452DAE

:1000200000000000C10B10280800C308031D192898

:10003000080009300000FF3E031D1A2800000000E0

:10004000C30B1928080083160313DA010230DB0002

:100050001030DC006F30DD00E001DD08031908001E

:100060005C08DE00DF015B18DE17DB185F1483130A

:100070005F1883175E0884000008E100E11B742804

Developed Program

Program for calling system:

It has three state:

Idle

Ringing

Connected

When the modem detects an incoming call it transmits the message “RING” at regular

intervals (approximately 2 seconds).

Steps to Write Program:

LCD Initializing

Sending AT+CLIP

Checking incoming call

Taking Number from Keypad

Speed Dialing

Sending ATA

Sending ATH

Main Program for calling

Taking Number from Keypad

Speed dialing

Receiving a Call Call termination

Main Program’s Tx Macro Main Program’s Rx Macro

Program for sending sms

Steps to Write Program:

Taking Number from Keypad

The AT command required to configure

this option is Message Format

command:

AT+CMGF=1

The AT command to send a text

message is:

AT+CMGS=<”number”>

Writing message

<CTRL-Z> to finish sending

Sending Number Sending Message

Program for receiving smsThe AT command required to achieve this is the New Message Indication

command:

AT+CNMI=2,2

Simulation and Result

Software Output

Speed dialling (out going call):

Hardware Output

Speed dialling call termination

If we press ‘*’ Key it will terminate by sending ATH command

Taking and Dialing a Number from Keypad

If we press the ‘5’ key on keypad a option will be appeared showing “Enter No” on Software LCD .than we have

to enter a mobile number which will be saved in a variable named “K_Buffer”.

if we press the ‘#’ Key on keypad, the entered number will be dialled By a AT command that is

“ATD01710036458;”

Incoming Call

Hardware output

Now if we press the ‘#’ key on the keypad the incoming call will be received by sending a AT command to

modem as “ATA”

If we press ‘*’ Key it will terminate.

Sending of sms: When we will press the ‘#’ key a AT command that is “AT+CMGS=<”01717405762”>

” is sent to the modem

Software Output Hardware output

Receiving of sms

The figure is showing received message from a remote mobile phone

Conclusion

There are three existing program has been modified separately for

calling, sending and receiving sms which is necessary to developed a

general phone.

But it works slowly because of during the execution of large program the

device faces some delay as its fixed clock speed and also for limitation of

LCD display and KEYPAD

For Your Time