radio frequency identification system

COURSE: Embedded systems and IC design

Passport number.: A01557194

UEL ID: U0957802

LECTURER: DR.Kanan

STUDENT: Aminu Iliyasu bugaje

Title: RFID based access system using 8051 and CPLD.

Aim

- To develop an RFID based system using microcontroller (8051) and CPLD.

Objectives

- To design an appropriate schematic diagram of the microcontroller based LCD interface

- To develop a C language program to interface and display the required information

- To simulate the requirements using appropriate software

- To write a VHDL code for the requirement using CPLD device

- To design the digital system using any of the design procedure.

- To simulate the code using Xilinx software to produce the appropriate results

- To compare the microcontroller based method with the CPLD based method.

Introduction

Wireless identification is an influential competency, and RFID exposes both a

physical object’s nature and position. With the advancement in embedded system and

communication, radio frequency identification radio frequency identification (RFID)

has been used in many application such as tracking, authentication system etc. The

RFID is a new technology that incorporates the use of electromagnetic coupling in the

radio frequency (RF) portion of the electromagnetic spectrum to uniquely identify an

object, animal, or person. An RFID system consists of three components: an antenna

and transceiver (often combined into one reader) and a transponder (the tag). The

antenna uses radio frequency waves to transmit a signal that activates the transponder.

When activated, the tag transmits data back to the antenna. RFID can read the tag using

RF, meaning that the RFID reader can be read from a distance, right through your

clothes, wallet, backpack or purse. In addition the RFID tag consists of unique ID for

each tag.

Moreover RFID technology is similar to the bar code identification systems;

however some big difference between RFID and bar code technology is that RFID does

not rely on the line-of-sight reading that bar code scanning requires working. While

reading the barcodes is time consuming, RFID readers can interrogate rates of more

than 40 tags in a second.

Additionally, lots of universities around the world nowadays use RFID for

various purposes such as student accessing system, student attendance systems. In such

universities the manual process of signing is eradicated because of its drawbacks such

as waste of time, the lecturer might forget the attendance sheet; student might also

forget to sign etc.

http://www.webopedia.com/TERM/B/bar_code.html

Lastly, RFID can be applied in many systems such as tracking livestock,

preventing forgery, controlling building accessing, supporting automated checkout,

developing smart home appliances, locating children etc. Therefore by using RFID,

abundant secured access systems can be established without investing vast amount of

money.

Microcontroller Design requirement

- Power supply:- A regulated +5v power is to be provided to the microcontroller

- Crystal speed:- A crystal of 11.0592MHz is needed for perfect baud rate generation and

timing

- Input/output pins: - The microcontroller has a total number of 32 I/O pin which the LCD

and the max232 will be connected to.

RFID Design requirement

- Name: RFID-IDR-232N

- Speed : 9600 baud RS232 serial interface

- Power: Fully operation with 5VDc power supply from USB port

- Data received: 12bytes of data received include start of heading, RFID ID and start of

text.

LCD interacing with AT89C51

Figure1. A 16x2 LCD interfaced to At89c51 microcontroller

The LCD used in the assignment is a (16x2) 16 pins; namely vcc,

vss, vee, en, rs, rw, the 8bit data pins and finally the backlight pins.

Vcc,Vss and VEE: Vcc and vss provides +5v and ground, respectively, while vee

(pin3) is used for lcd contrast adjustment.

Rs, Register select: The RS pin is used for the selection of either command is to be

send to the LCD or data is to be send to the LCD. If RS=0, the instruction command

code register is selected, allowing the user to send commands such as clear display,

cursor blink, cursor goto home etc. If RS=1 the data register is selected, allowing the

user to send data to be data to be displayed on the LCD such as Ascii code for A-Z or

0-9.

R/W, read/write: R/W input allows the user to write information to the LCD or read

information from it. R/W=1 when reading; R/W=0 when writing.

En, enable: The enable pin is used by the LCD to handle information existing to its

data pins. When data is delivered to data pins, a high to low pulse must be applied to

this pin inorder for LCD to latch in the data pins. (Mazidi 2000)

D0-D7 (8bit pins)

The 8bit data pins, are used to send information to the LCD such as Ascii code

for the letters a-z or 0-9 while making RS=1.

C language code to for LCD interfaced to 8051.

Functions for 89c51 sending data to LCD

void send_data(unsigned char send_data) //Lcd data function

lcd_data_pin=send_data;

en=1; // enable high

rs=1; // register select is high

rw=0; // write in lcd

generate_delay(1);

en=0; // enable is off

Function for commanding the LCD.

Function for initializing the LCD.

void send_command(unsigned char send_comm) //Lcd command funtion

lcd_data_pin=send_comm;

en=1;

rs=0;

rw=0;

generate_delay(1);

en=0;

void lcd_ini() //Function to initialize the LCD

send_command(0x38); // 2 line 5x7 matric (D0-D7, 8bit)

generate_delay(1);

send_command(0x0F); // Display on, cursor blinking

generate_delay(1);

send_command(0x80); //cursor to begin at 1st line, position 1

generate_delay(1);

send_command(0x01); //clear LCD.

Serial communication

The At89c51 has been equipped with Universal Asynchronous reception

and transmission functionality (UART). The asynchronous serial data communication

is widely used for character-oriented transmission where each character is placed in

between the start and stop bits called framing.

The 8051 has two pins that are used specifically for transferring and

receiving data serially; there two pins are called TxD and RxD having TTL

compatibility, therefore a driver (MAX 232 is required to make them RS232

compatible. (Mazidi 2000)

Baud rate consideration is one of the essential elements to put in place

while using the microcontroller serial communication pins. The Baud rate is the speed

at which data is transmitted serially. That is the number of bits transmitted or received

per second. It is generally expressed in bps (bits per second). AT89C51 microcontroller

can be set to transfer and receive serial data at different baud rates using software

instructions. Timer1 is used to set the baud rate of serial communication for the

microcontroller. Therefore Timer1 is used in mode2 which is an 8-bit auto reload mode.

To get baud rates well-matched with the RFID, TH1 should be loaded with the values

as shown: (Mazidi 2000)

Baud Rate (bps) TH1 (Hex value)

9600 FD

4800 FA

2400 F4

1200 E8

In this assignment the baud rate used is 9600bps.

8051 Serial communication Registers

- SBUF: is an 8bit register used mainly for serial communication. For a byte to be

transferred via the TxD line, it must be placed in the SBUF register. The SBUF holds

the byte of data when it is received by 8051 RxD line.

successfully sent or received. (Mazidi 2000)

- SCON: is an 8bit register used to program the start bit, stop bit and data bit etc.

SM0 SM1 SM2 REN TB8 RB8 TI RI 0 1 0 1 0 0 0 0

-TMOD register is a 8bit register, the lower bits are for timer0 and upper 4 bits are for

timer1. In this each case, the lower 2bit are used to the timer mode and the upper 2 bit

to specify the operation.

TCON (timer control) register is an 8 bit register, the upper four bit are used to store

the TF and TR bits of timer0 and 1. The lower 4 bit are set aside for controlling the

interrupt bits

TF1 TR1 TF0 TR0 IE1 IT1 IE0 IT0

0 1 0 0 0 0 0 0

(Mazidi 2000)

Gate C/T

M1 M0 Gate C/T

M1 M0

0 0 1 0 0 0 0 0

Programming the 8051 serial communication

When programming 8051 to either receive or transmit bytes serially,

- The TMOD reigister is loaded with value 0x20, indicating the used of timer 1 in mode2(8

bit auto reload).

- TH1 is load to set the baud rate

- SCON register is load value 0x50, indicating serial mode 1, where an 8bit data is framed

with start and stop bits,

- TR1 must be set to 1 to start timer 1

- RI or TI are cleared by TI=0 or RI =0 instruction

- When reception is completed RI =1, the SBUF has the byte.

Sample function code for initializing 8051 UART

void serial_in()

SCON=0x50;

TR1=1;

TMOD=0x22;

TL1=TH1=0XFD;

TH0=0xA5;

TL0=0xFE;

//TR0=1;

// EA=1;

//ES=1; // Trigger Timer 1

IE=0x92;

Function for microcontroller to receive the RFID card number using interrupt

void recieve() interrupt 4 // Function to recieve data serialy from RS232

recieve_id[rec_count]=SBUF;

RI=0; // Reset the serial interrupt after recieving the byte

rec_count++;

Function for microcontroller to count the time using interrupt 1

void timer0(void) interrupt 1

count=count+1;

if(count==40)

send_command(0xc3);

lcd_ascii(hr);

send_data(':');

lcd_ascii(min);

send_data(':');

lcd_ascii(sec);

count=0;

generate_delay(100);

sec=sec+1;

if(sec>59)

sec=0;

min=min+1;

if(min>59)

min=0;hr=hr+1;if(hr>23)hr=0;

System Flowchart

The flowchart gives a brief overview on how the system program works

out. The flowchart is shown below.

Figure 2 Entire system flowcharts

START

Configure all ports, UART and devices

is Receive =

card_number

Display scan card on LCD

message

No Yes

Scan card on RFID reader

Display Access granted and

student info.

Display Access denied

Wrong id

#include<reg51.h>

sfr lcd_data_pin=0x80;//p0 port

sbit rs=P2^4; // Register select pin

sbit rw=P2^5; // Read Write pin

sbit en=P2^6; // Enable pin

unsigned char recieve_id[12];

unsigned char rec_count=0;

unsigned int hr=0; int sec=0; int min=0;

int i,count;

sbit led=P2^0;

sbit led2=P2^1;

unsigned char message[]=" Name:Aminu bugaje Age:22 school:Legenda ";

void generate_delay(unsigned int x) //Function to provide delay

int i,j;

for(i=0;i<x;i++)

for(j=0;j<1275;j++);

void send_command(unsigned char send_comm) //Lcd command funtion

lcd_data_pin=send_comm;

en=1;

rs=0;

rw=0;

generate_delay(1);

en=0;

void send_data(unsigned char send_data) //Lcd data function

lcd_data_pin=send_data;

en=1;

rs=1; // register select

rw=0;

generate_delay(1);

en=0;

send_str(unsigned char *data_) //Function to send string

int l;

for(l=0;data_[l]!=0;l++)

send_data(data_[l]);

return 0;

void lcd_initialization() //Function to initialize the LCD

send_command(0x38);

generate_delay(5);

send_command(0x0F);

generate_delay(5);

send_command(0x80);

generate_delay(5);

void lcd_ascii(unsigned int display)

int y;

y=display/10;

send_data(y+48);

y=display%10;

send_data(y+48);

void timer0(void) interrupt 1

count=count+1;

if(count==40)

send_command(0xc3);

lcd_ascii(hr);

send_data(':');

lcd_ascii(min);

send_data(':');

lcd_ascii(sec);

count=0;


sec=sec+1;

if(sec>59)

sec=0;

min=min+1;

if(min>59)

min=0;hr=hr+1;if(hr>23)hr=0;

void recieve() interrupt 4 // Function to recieve data serialy from RS232

recieve_id[rec_count]=SBUF;

RI=0; // Reset the serial interrupt after recieving the byte

rec_count++;

void check_card()

if(( recieve_id[1]=='0')&&( recieve_id[2]=='0') &&( recieve_id[3]=='1')&&(

recieve_id[4]=='5')&&( recieve_id[5]=='9')&&( recieve_id[6]=='4')&&(


recieve_id[10]=='0'))

led2=1;


send_command(0x01);

send_command(0xc0);

send_str("Access granted");


led2=0;

send_command(0x01);

send_command(0x80);

send_str("Name:Aminu bugaje");

send_command(0xc3);

send_str("ID:u0957802");


send_command(0x01);

send_command(0x80);

send_str("DOB:23/01/90");

send_command(0xc0);

send_str("22yrs");

send_command(0xc7);

lcd_ascii(hr);

send_data(':');

lcd_ascii(min);

send_data(':');

lcd_ascii(sec);


send_command(0x01);

send_str("legenda kolej");

send_command(0x01);

send_str("legenda kolej");


send_command(0x01);

send_command(0x01);

send_command(0x80);

send_str("You came at:");

send_command(0xc3);


lcd_ascii(hr);

send_data(':');lcd_ascii(min);send_data(':'); lcd_ascii(sec);

generate_delay(200);send_command(0x01);

else if(( recieve_id[1]=='1')&&( recieve_id[2]=='1') &&( recieve_id[3]=='1')&&(



recieve_id[10]=='0'))

led2=1;


send_command(0x01);

send_command(0xc0);

send_str("Access granted");


led2=0;

send_command(0x01);

send_command(0x80);

send_str("Name:Aewal bugaje");

send_command(0xc3);

send_str("ID:u0957802");


send_command(0x01);

send_command(0xc0);

send_str("age:25yrs");

send_command(0xc9);lcd_ascii(hr);send_data(':');lcd_ascii(min);send_data(':');lcd_ascii(

sec);generate_delay(400);send_command(0x01);send_str("inti

kolej");generate_delay(400);send_command(0x01);send_command(0x01);send_comma

nd(0x80);send_str("You came

at:");send_command(0xc3);generate_delay(100);lcd_ascii(hr);send_data(':');

lcd_ascii(min);send_data(':');lcd_ascii(sec);generate_delay(200);send_command(0x01);

else

led2=1;


send_command(0x01);

send_command(0x84);

send_str("wrong id!!!");

send_command(0xc3);

send_str("Access denied!!!");

generate_delay(200); led2=0;

void serial_in()

SCON=0x50;

TR1=1;

TMOD=0x22; //Enable Timer 1

TL1=TH1=0XFD;

TH0=0xA5;

TL0=0xFE;

TR0=1;

// EA=1;

//ES=1; // Trigger Timer 1

IE=0x92;

void main()

unsigned char k;

lcd_initialization();

serial_in();

send_command(0x80); //Place cursor to second position of first line

send_str("receiver waiting");


while(1)

send_command(0x01);

send_command(0x80); //Place cursor to second position of first line

send_str("receiver waiting");

send_command(0xc4); //Place cursor to second position of first line

send_str("scan please");

while(rec_count!=12);

send_command(0x01);

send_command(0xC1); //Place cursor to second position of second line

for(k=1;k<11;k++)

send_data(recieve_id[k]);

rec_count=0;

check_card();

Complex programmable logic device (CPLD)

A complex programmable logic device (CPLD) comparises of multiple blocks of

logical gates on a single chip with internal wiring resource to connect the circuit blocks

and a bank of macrocells. Each logical circuit block is similar to a PLA or a PAL. The

logical gates are reprogrammable with the capabilities of performing multitude of logical

functions. Macrocells are functional blocks that perform combinational or sequential

logic, and also have the added flexibility for true or complement, along with varied

feedback paths. (Brown 2005 pp 101).

CPLD execute a variety of valuable tasks in systems design due to their unique

capabilities and as the market leader in programmable logic solutions, where Xilinx

provides a total solution to a designer’s CPLD needs

Explain the requirements if this had to be designed using CPLD.

Considering the features and benefits of using CPLDs can help enable ease of

design, lower development costs, and speed products to market. When designing systems

with CPLD, certain things must be put in place such as its logic density and I/O’s,

performance, voltage and power and finally packaging.

This section is to explore the flexibility and capability of CPLD for creating an

RS232 serial interface. The CPLD is not same as the microcontroller where an inbuilt

UART is available in the microcontroller. In this case the UART hardware module has to

design using very high speed hardware descriptive language VHDL which will lead to

the accomplishment of the RFID based system using CPLD.

The main goal will be to send string of characters or numbers from an RFID

reader to a CPLD Dev. Board and display on an LCD.

Base on the assignment requirement, the following devices are needed:

- Xilinx CoolRunner-II CPLD’s chip with complete power supply and reset circuit

- Clock generator

- JTAG programmer

- Level translator for LCD and MAX232

Schematic summary

The main parts in the schematic for this assignment are the CPLD Dev Board,

16x2 LCD, power supply, MAX232, JTAG, Level translator.

Design requirements.

Power regulation

The power regulation circuit converts the +12v from the adaptor to a steady +3.3v

output to the CPLD.

CPLD Dev Board

The development board contains a PLCC Xilinx cool runner II CPLD chip with

power supply section and JTAG connectors for programming. The Xilinx cool runner II

CPLDs deliver the high speed and ease of used associated with the XC9500/XL/XV

CPLD family with extremely low power versality of the XPLA3 family in a single

CPLD. This means that the exact same part can be used for high speed data

communications etc.

16X2 LCD connection

The 16x2 LCD makes 11 digital I/O connections to the CPLD when used in 8 bit

mode. The rest of the LCD’s pin are power connection and contrast from the 10kΩ

potentiometer.

Clock generator

Mostly a clock above 10MHz will be fine for this assignment. The clock is used

as a timing device.

` MAX 232 circuit

The RS232 interface circuit consists of the CPLD, its 25.175MHz crystal clock

and the MAX232. The max232 translates the +12V higher voltage RS232 signals into

TTL logic that can be understood by the CPLD.

Level translator.

The CPLD device provides an output voltage of 3.3volts whereas the LCD and

the Max232 require 5v to operate, therefore the use of a level translator is necessary for

this design. The MAX30xxx family was chosen for this purpose.

The MAX3000E/MAX3001E/MAX3002–MAX3012 8channel level translators

provide the level shifting necessary to allow data transfer in a multi voltage system.

Externally applied voltages, VCC and V, set the logic levels on either side of the device.

Logic signals present on the VLL side of the device appear as a higher voltage logic

signal on the V side of the device, and vice-versa. (Max3004 datasheet).

Digital system using Dip trace software

Complete circuit interfaced to CPLD via Level translator

JTAG programmer interfaced to CPLD via TCK,TDI,TDO and TMS pins

MAX232 interfaced to CPLD via Level translator

LCD interfaced to CPLD via Level translator.

VHDL code for the requirement.

The VHDL code the RFID based system is shown below. As can be seen, it consists of

ENTITY, which is a description of the pins (PORTS) of the circuit, and of an

ARCHITECTURE, which describes how the circuit should function.

-- Name: Aminu iliyasu bugaje

-------------------------------------------------------

library ieee;

use ieee.std_logic_1164.all;

use ieee.std_logic_unsigned.all;

entity lcdass is

port ( receiver_input :in std_logic;

receiver_cleaar :out std_logic;

LCDDATAPORT : out std_logic_vector(7 downto 0);

LCD_register_select : out std_logic;

LCD_read_write : out std_logic;

LCD_enable : out std_logic;

reset :in std_logic;

---clk in std_logic;

receiver_clock :in std_logic;

user_identity_string_received:in std_logic;

data_received : out std_logic_vector (7 downto 0);

enable_reception :in std_logic

); end lcdass;

architecture rfid_assignment of lcdass is

signal CARD_IDENTITY0: std_logic_vector(7 downto 0);










signal reception_reister :std_logic_vector (7 downto 0);

signal reception_counter :std_logic_vector (3 downto 0);

signal count_received :std_logic_vector (3 downto 0);

signal reception_error_in :std_logic;

signal receiver_overflow:std_logic;

signal received_count1:std_logic;

signal received_count2:std_logic;

signal receiver_busy :std_logic;

signal receiver_cleared :std_logic;

Signal uart_pnt:std_logic_vector(3 downto 0);

signal Reception_buffer_register :std_logic_vector(32 downto 0);

begin

-- UART reception code

process (receiver_clock , reset) begin

if (receiver_busy = '1') then

reception_counter <= reception_counter + 1;

if (reception_counter = 7) then

if ((received_count2= '1') and (count_received = 0)) then

receiver_busy <= '0';

else

count_received <= count_received + 1;

if (count_received > 0 and count_received < 9) then

reception_reister(conv_integer(count_received) - 1) <= received_count2;

end if;

if (count_received = 9) then


if (reset = '1') then

reception_reister <= (others=>'0');

data_received <= (others=>'0');

reception_counter <= (others=>'0');

count_received <= (others=>'0');

reception_error_in <= '0';

receiver_overflow <= '0';

receiver_cleared <= '1';

received_count1 <= '1';

received_count2 <= '1';


for j in 0 to 50 loop

Reception_buffer_register(j)<='0';

end loop;

uart_pnt<="0000";

elsif (rising_edge(receiver_clock )) then

received_count1 <= receiver_input;

received_count2<= received_count1;

if (user_identity_string_received= '1') then

data_received <= reception_reister;


end if;

if (enable_reception = '1') then -- data is received when receiver=1;

if (receiver_busy= '0' and received_count2= '0') then

receiver_busy<= '1';

reception_counter <= X"1";

count_received <= X"0";

end if;

--

if uart_pnt="0000" then

CARD_IDENTITY0(0)<=reception_reister(0);CARD_IDENTITY0(1)<=reception_reister(0);




end if;






end if;

if



CARD_IDENTITY2(2)<=reception_reister(0);CARD_IDENTITY2(3)<=reception_reist

er(0);


er(0);


er(0);

end if;

if

uart_pnt="0011" then





end if;






end if;






end if;






end if;






end if;






end if;





CARD_IDENTITY9(6)<=reception_reister(0);CARD_IDENTITY9(7)<=reception_reister(0)

end if;


uart_pnt<="0000";

-- code to compare the RFID card number with the stored coded number

if(card_identity0=0 and card_identity1=0 and card_identity2=1 and

card_identity3=5 and card_identity4=0and card_identity5=1 and

card_identity6=5 and card_identity7=0 and card_identity8=1 and card_identity9=5) then

--- if correct then dispaly students info on lcd AMINU, age, school

--initialize LCD

LCD_register_select<='0'; LCD_read_write

<='0';LCDDATAPORT<="00111000";LCD_enable<='1';

for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write command 0x38



for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write command 0x0e







--SEND MY NAME TO THE LCD "AMINU"



for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data A



for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data M



for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data I



for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data N



for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data U

--SEND MY UEL ID TO THE LCD "u095782"



for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data U



for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data 0



















--SEND MY AGE TO THE LCD "AGE:22 YEARS"






for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data G



for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data E



for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data :









for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data Y









for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data R

--SEND MY COLLGE: TO THE LCD " COLLEGE:LINTON"



for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data C



for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data O



for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data L









for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data G






for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data :






for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data I






LCD_register_select<='1'; LCD_read_write <='0';LCDDATAPORT<="01010100";LCD_enable<='1';

for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data T


for j in 1 to 10000 loop end loop;LCD_enable<='0'; -- write data O



end if;

end if;

if (received_count2= '0') then

reception_error_in<= '1';

else


reception_error_in<= '0';

if (receiver_cleared = '1') then

receiver_overflow<= '0';

else

receiver_overflow<= '1';

end if;

end if;

end if;

end if;

end if;

end if;

end if; if (enable_reception = '0') then


end if; end if; end process; receiver_cleaar <= receiver_cleared;

end rfid_assignment;

Comparison between the Microcontroller based and the CPLD based system.

Microcontroller CPLD

Microcontroller has built in

CPU, and other peripherals

such as ADC, UART, and

PWM etc. Therefore the

inbuilt UART was simply

configured using C language

for the RFID application.

CPLD only consists of logical

blocks of gates that can be

rewired electrically using Very

high speed hardware descriptive

language. Therefore the UART

hardware has to be built through

VHDL program for the RFID

application.

Microcontroller is

programmed by software

approach which can be C

language, assembly language

etc. suited for medium

performance and control.

CPLDs are programmed based

on Hardware approach called

VHDL language suited for very

fast applications.

Microcontroller executes

instruction by instruction

(sequentially).

Microcontroller is moderately slow

for processing complex system

applications

CPLD supports concurrent

logical execution of instruction.

CPLDs are used where low

power and high speed are

required.

Xilinx simulation using testbench approach

Lcd simulation.

Uart code and LCD code together

Lcd and UART together

LCD and UART together

Conclusions

Firstly in the first section of the assignment, an 8051 microcontroller based RFID

system was built with an RS232 interface via max232 which worked perfectly, while the

second section was by using a CPLD device where hardware module for an RS232

interface was made using VHDL and by using the code the CPLD was able to receive

data’s from an RFID reader. These data’s where translated and displayed on an LCD

display which was achieved successfully.

Additionally, the difference between microcontroller based design and the CPLD

design was that, the microcontroller had its in built CPUs with other peripherals such are

UART, with distinct input/output ports programmed using software approach to instruct

the CPU based on the commands while CPLD consists of group of isolated number of

logical gates which are attached together using VHDL code used for complex and high

speed application.

Lastly, RFID can be applied in many systems such as tracking livestock,

preventing forgery, controlling building accessing, supporting automated checkout,

developing smart home appliances, locating children etc. Therefore by using RFID,

abundant secured access systems can be established without investing vast amount of

money.

Reference

a. Mazidi.M.A., Mazidi J.G., 2000,“8051 Microcontroller and Embedded Systems”,Upper

Saddle River, N.J. Pearson Edu. Inc.

b. Brown.S, Vranesic.Z. , 2005,” Fundamentals of Digital Logic with VHDL Design”, 2nd

Edition, Mc Graw Hill International Edition.

c. Volnei A. Pedroni, 2004, Circuit Design with VHDL, 1st ed. MIT Press Cambridge,

Massachusetts London, England

Appendix

Keil Uvsion

radio frequency identification system

Documents