This document describes a smart card prepaid energy meter system using GSM. The system includes an ARM microcontroller that takes readings from an energy meter and displays it on an LCD. It also sends the reading to the user's phone via text message through a GSM modem. The hardware requirements include components like the microcontroller, GSM modem, LCD, LEDs, resistors, capacitors, transformer, regulator, relay, energy meter and lamp. The software used is the KEIL compiler and embedded C. It allows reducing manual efforts to read energy meters and provides a cost effective solution with reduced manpower.

1. SMART CARD PREPAID ENERGY
METER USING GSM

2. ABSTRACT
 The main objective of the project is to develop a prepaid
energy meter.
 The microcontroller takes the reading from the energy meter
and displays the reading on the LCD. The reading of the energy
meter is also sent to the cell phone of the user by a message
through GSM modem.
 This project is powered by an on-board power supply takes
the ac power and converts it into dc power that is fed to on-board
devices and integrated circuits.

4. HARDWARE
REQUIREMENTS:
 ARM MICROCONTROLLER
 GSM MODEM
 LCD
 LED
 RESISTORS
 CAPACITORS
 DIODES
 TRANSFORMER
 REGULATOR
 RELAY
 ENERGYMETER
 LAMP
SOFTWARE
REQUIREMENTS:
 KEIL COMPILER
 EMBEDED C

5. HARDWARE REQUIREMENTS
ARM MICROCONTROLLER
 ARM9TDMI based high-performance 32-bit RISC
micro-controller with thumb extensions. 16kb on-chip
ROM, 256kb SRAM, 32kb instruction cache, 32kb
data cache, clock up to 208 MHz 3 channel
multiplexed 10-bit ADC, RTC, and 32-bit general
purpose high speed timer.
 Two UART’S, one with full modem interface, two
I2C serial interfaces, two SPI serial interfaces. CPU
clock up to 60 MHz

6. ENERGY METER:
• An energy or electric meter is a device that measures the amount of
electrical energy consumed by a residence, business, or an
electrically-powered device.
• Electric meters are typically calibrated in billing units, the most
common one being the kilowatt hour.

7. PIN DIAGRAM OF ARM MICROCONTROLLER

8. SERIAL COMMUNICATION
• used for all long-haul communication
• Cables that carry serial data
• RS232 carries serial data in between micro controller
and MODEM through DB9 connector

9. MAX 232:
The MAX232 is an integrated circuit that converts signals from
an RS-232serial port to signals suitable for use in TTL
compatible digital logic circuits.
The MAX232 is a dual driver/receiver and typically converts
the RX, TX, CTS and RTS signals .
When a MAX232 IC receives a TTL level
to convert, it changes a TTL Logic 0 to
between +3 and +15V, and changes TTL
Logic 1 to between -3 to -15V, and vice
versa for converting from RS232 to TTL.

10. DB9 CONNECTOR:
• The DB9 (originally DE-9) connector is an analog 9-pin plug of
the D-Sub miniature connector family (D-Sub or Sub-D).

11. A relay is an electrically operated switch. Many relays
use an electromagnet to mechanically operate a switch, but
other operating principles are also used, such as solid-state
relays.
Relays are used where it is necessary to control a circuit
by a low-power signal (with complete electrical isolation
between control and controlled circuits), or where several
circuits must be controlled by one signal.
Relays with calibrated operating characteristics and
sometimes multiple operating coils are used to protect
electrical circuits from overload or faults
RELAY:

12. GSM COMMUNICATION
 The term GSM usually means the GSM standard
and protocols in the frequency spectrum around
900MHz.
 Mobile Station:
The MS is the physical equipment used by a
subscriber, most often a normal hand-held cellular
telephone.
 Base transceiver station:
The BTS comprises the radio transmission and
reception devices, and also manages the signal
processing related to the air interface.

13. GSM MODEM:
A GSM modem is a specialized type of modem which accepts a SIM
card, and operates over a subscription to a mobile operator, just like a
mobile phone.
From the mobile operator perspective, a GSM modem looks just like
a mobile phone.
When a GSM modem is connected to a computer, this allows the
computer to use the GSM modem to communicate over the mobile
network.
While these GSM modems are most frequently used to provide
mobile internet connectivity, many of them can also be used for sending
and receiving SMS and
MMS messages.

14. IR LED:
 An IR LED, also known as IR transmitter, is a special purpose LED
that transmits infrared rays in the range of 760 nm wavelength.
The appearance is same as a common LED. Since the human eye
cannot see the infrared radiations.
The camera can show us the IR rays being emanated from the IR LED
in a circuit.

15. LIQUID CRYSTAL DISPLAY (LCD):
Most common LCDs connected to the microcontrollers are 16x2 and
20x2 displays.
This means 16 characters per line by 2 lines and 20 characters per line
by 2 lines, respectively.
DISPLAY UNIT

16. LCD BACKGROUND:
If an 8-bit data bus is used the LCD will require 11 data lines
(3 control lines plus the 8 lines for the data bus)
The three control lines are referred to as EN, RS, and RW
EN=Enable (used to tell the LCD that you are sending it data)
RS=Register Select (When RS is low (0), data is treated as a command)
(When RS is High(1), data being sent is text data )
R/W=Read/Write (When RW is low (0), the data written to the LCD)
(When RW is high (1), the data reading to the LCD)

17. SOFTWARE REQUIREMENTS
Keil an ARM Company makes C compilers, macro assemblers,
real-time kernels, debuggers, simulators, integrated environments,
evaluation boards, and emulators for ARM7/ARM9/Cortex-M3,
XC16x/C16x/ST10, 251, and 8051 MCU families.
Compilers are programs used to convert a High Level Language
to object code. Desktop compilers produce an output object code for
the underlying microprocessor, but not for other microprocessors
KEIL COMPILER:

18. AT COMMANDS:
 AT commands are instructions used to control a modem.
 AT is the abbreviation of Attention. Every command line starts with
"AT" or "at". That's the reason, modem commands are called AT
commands.
 Many of the commands that are used to control wired dial-up
modems, such as ATD (Dial), ATA (Answer) supported by MODEM.
Besides this common AT command set, GSM modems and
mobile phones support an AT command set that is specific to the GSM
technology, which includes SMS-related commands like AT+CMGS
(Send SMS message), AT+CMSS (Send SMS message from storage),
AT+CMGL (List SMS messages) and AT+CMGR (Read SMS
messages).

19. • Using this project we can reduce the manual
Efforts to take the readings from the energy
Meter which is cost effective solution .
• Reduces man power.
• It is user friendly and we can enhance this
Project ,in which an electricity department can
Send message to the consumer about the
billing information.
CONCLUSION

20. REFERENCES
[1] M I Tibbenham, “Implementing a Pre-payment System” IEE
International Congress on Metering and Tariffs for Energy
Supply, Birmingham, UK, 1999, pp 251-257.
[2] Muhammad Faheem Khan, Ahmed Zoha, and Rana Liaqat
Ali ‘’Design and
Implementation of Smart Billing and Automated Meter Reading
System for Utility Gas ‘’Proc. in IEEE Conference on
Information and Emerging Technologies, 2007, pp1-6
[3] KwanB H, M Moghawemi ‘’PIC Based Smart Card
Prepayment System‘’ Proc. in IEEE Student Conference on
Research and Development, Malaysia, 2002, pp 440-443

21. Thank You