ABAP/4 provides some interactive events on lists such as AT
LINE-SELECTION (double click) or AT USER-COMMAND (pressing a
button). You can use these events to move through layers of
information about individual items in a list. 

Drill down report is nothing but interactive
report...drilldown means above paragraph only.

Perl - Test

1.Write a perl script to display command line arguments
separated by new line
foreach $arg (@ARGV) {
	print $arg . "\n";
}
2.Write a perl script to Store and retrieve records in a
plain text file
store
#Copying contents of one file into another file
# If another files exists, then its overwritten if not
exists then created

unless (open(INFILE, "file1.txt")) {
 die ("cannot open input file file1\n");
}
unless (open(OUTFILE, ">outfile.txt")) {
 die ("cannot open output file outfile\n");
}
$line = <INFILE>;
while ($line ne "") {
 print OUTFILE ($line);
 $line = <INFILE>;
}

retrieve

if (open(MYFILE, "file1.txt")) {
$line = <MYFILE>;
while ($line ne "") {
	print ($line);
	$line = <MYFILE>;
}
}

3.Illustrate the passing by reference and passing by value
with separate examples each.
$value = 10;
print " passing by value: $value \n";


$pointer = \$value;
print " Pointer Address is $pointer of value $value \n";
print " passing by reference: $$pointer \n";

4.Show use of typeglob with a example


sub generate_greeting {
     my ($greeting) = @_;
        sub { print "$greeting world\n";}
}
$rs = generate_greeting("hello");

&$rs();

# Instead of invoking it as &$rs(), give it your own name.
*greet = $rs;
greet();    # Equivalent to calling &$rs(). Prints "hello
world\n"

#Typeglobs are used to create alises of symbols.
# They are easy to use, they can be alised to ordinary
references. See above code

5.Describe the use of bless() in constructors
bless function is same like a fork function,that si it
creats a copy of the instance of the class and returns
the reference of that obj.  its mandatory for a constructor
to have a bless function.

package Animal;

sub new{
	my $class = shift;
	my $self = {};
	$self->{NAME} = undef;
	bless($self,$class);
	return $self;
}

sub eat{
	return "Eats animal food\n";
}

6.Show an example of reusable object in Perl with a short script
use person;
use Employee;

my $empl = Employee->new();
$empl->name("Jason Bourn");
$empl->age(25);
$empl->salary(40);
printf "%s is age %d. Salary %d\n", $empl->name,
$empl->age,$empl->salary;

7.Write a small object oriented application to read and
write text files.


8.Write a script to store web page from a given Internet
location.

# Get and print out the headers and body of the CPAN homepage
    use HTTP::Lite;
    $http = new HTTP::Lite;
    $req = $http->request("http://www.cpan.org/")
        or die "Unable to get document: $!";
    die "Request failed ($req): ".$http->status_message()
      if $req ne "200";
    @headers = $http->headers_array();
    $body = $http->body();
    foreach $header (@headers)
    {
      print OUTFILE("$header$CRLF");
      print OUTFILE("$CRLF");
      print OUTFILE("$body$CRLF");
}

    # POST a query to the dejanews USENET search engine
    use HTTP::Lite;
    $http = new HTTP::Lite;
    %vars = (
             "QRY" => "perl",
             "ST" => "MS",
             "svcclass" => "dncurrent",
             "DBS" => "2"
            );
    $http->prepare_post(\%vars);
    $req = $http->request("http://www.deja.com/dnquery.xp")
      or die "Unable to get document: $!";
    print "req: $req\n";
    print $http->body();

9.Illustrate a simple http auth with a working example.

10.Write a script to read and show a XML file with nodes.
#!/usr/bin/perl

# use module
use XML::Simple;

# create object
$xml = new XML::Simple;

# read XML file
$data = $xml->XMLin("data.xml");

# access XML data
print "$data->{name} is $data->{age} years old and works in
the $data->{department} section\n";

11.Describe use of ^ and $ pattern matching charectors.
beginning of string ^ 
end of string $


^abc
abc at the beginning of the string 
abc$
abc at the end of the string 
12.Write a script to print a hash with keys
		#!/usr/bin/perl

print "Hash \n\n";

# DEFINE A HASH
%coins = ("Quarter", 25, "Dime", 10, "Nickel", 5);

# PRINT THE HASH
print %coins , "\n"; #See how it prints

13.Write a script to add user entered values to a array
#!/usr/bin/perl
1.$total = 0;
2.
3.@numbers=&getnumbers;
4.foreach $number (@numbers) {
5.	$total += $number;
6.}
7.print ("the total is $total\n");
8.
9.sub getnumbers {
10.	$line = <STDIN>;
11.	$line =~ s/^\s+|\s*\n$//g;
12.	@numbers = split(/\s+/, $line);
13.}
14.write a script to make sum of a numeric array elements
@array =(1,2,3,4,5);

$total=0;
foreach $array(@array){
$total+=$array;
}

print $total;
15.Describe and write foreach loop with example.

foreach $arg (@ARGV) {
	print $arg . "\n";
}

Mini Project (Case study)

1) Name: Displaying of Analog, Digital Signals, testing of 
LEDs, CAN communication and read/write EEPROM on the hyper 
terminal based on the user selection.

Project: The following peripherals are used based on the 
user input. 

1)	Read ADC Values
2)	LED Test
3)	EEPROM Test
4)	CAN Communication Test


Architecture:


 
Description:

The following menu shall be displayed on the hyper-terminal 
of PC
l
Main Menu:
1)	Read ADC Values
2)	LED Test
3)	EEPROM Test
4)	CAN Communication Test
5)	Reset the system
6)	Stop

Enter the Choice: 

The user shall select the option, based on the selection 
respective peripheral shall be tested and result shall be 
displayed on the hyper-terminal. For CAN, the message shall 
be received on the trace window of CANalyzer or CANoe. 

The menu and the result shall be displayed on the hyper-
terminal with the help of UART communications.

For selection 1 (Read ADC Values):

After selecting this option, the ADC shall be read every 
500ms and the result shall be displayed on the hyper-
terminal along with the time stamps. 

For selection 2 (LED Test):

When this option is selected then following LED menu shall 
be displayed and based on the input value respective LED 
shall be switched on with 50% duty cycle (200Hz frequency). 
The position of the LED shall be remembered and after 
reset, the same LED shall be switched on.

LED Menu: 
Enter LED number to switch on [1-8]: 

For selection 3 (EEPROM Test):

When this option is selected, following sub menu shall be 
displayed,

EEPROM Menu:

1)	EEPROM Write Data
2)	EEPROM Read Data
Enter the choice: 

1) After selecting the ‘EEPROM Write Data’ option, the 
software shall prompt for the data from user (10 bytes) as 
shown below and it shall be written in to the 10-succesive 
location of EEPROM. After writing it to EEPROM, checksum 
(16 bit checksum) shall be calculated for the written data 
and it shall be displayed on the hyper-terminal as Checksum 
Result: 0xXXXX. It shall store the checksum in the EEPROM.

Enter Data: 

2) After selecting the ‘EEPROM Read Data’ option, the 
software shall read the written data and checksum from 
EEPROM. The read data shall be displayed on the hyper-
terminal along with the memory address as shown below

	Memory Address: 0xXXXX
	Data: 0xXX

And checksum as

 	Memory Address: 0xXXXX
	Checksum: 0xXXXX

For selection 4 (CAN Communication Test):

After selecting this option, following sub menu shall be 
displayed.

CAN Menu:

1)	CAN Transmit
2)	CAN Reception
Enter the choice:

Based on the above selection following functionality shall 
be implemented

CAN Transmit:
When this option is selected, following CAN frame shall be 
transmitted periodically (500ms) with the standard frame id 
and 8 bytes of data. The frame id and data shall start from 
zero and shall be incremented for each message.

For 1st message:
Message Id (standard id): 0x00
Data: 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0

For 2nd  message:
Message Id (standard id): 0x01
Data: 0x01 0x01 0x01 0x01 0x01 0x01 0x01 0x01
….
….

For Nth message:
Message Id (standard id): 0x0N
Data: 0x0N 0x0N 0x0N 0x0N 0x0N 0x0N 0x0N 0x0N

CAN Reception:
Whenever the data is transmitted from the host (PC) with 
the help of CANalyzer or CANoe, the received message shall 
be displayed on the hyper-terminal with time stamp along 
with frame id and data.

If the following message is received from the host then 
corresponding LED’s shall be switched on.

The frame id, data and other details as given below,

Frame Id: 0xFF
Data: 0xXX 0x0 0x0 0x0 0x0 0x0 0x0 0x0

This message shall override the previous status of the LEDs.

Details of first byte: 

Each bit of first data byte represent the corresponding LED 
and it’s status.
i.e. 
Bit0 corresponds to LED0
Bit1 corresponds to LED1
Bit2 corresponds to LED2
Bit3 corresponds to LED3
Bit4 corresponds to LED4
Bit5 corresponds to LED5
Bit6 corresponds to LED6
Bit7 corresponds to LED7



MSB							
				LSB
Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 
0
LED7
0 – Off
1 – On	LED6
0 – Off
1 – On	LED5
0 – Off
1 – On	LED4
0 – Off
1 – On	LED3
0 – Off
1 – On	LED2
0 – Off
1 – On	LED1
0 – Off
1 – On	LED0
0 – Off
1 – On


If the particular bit is ‘1’ then switch on the 
corresponding LED, if it is ‘0’ then switch off the 
corresponding LED.

For e.g: For the message id: 0xFF and Data: 0x05 0x0 0x0 
0x0 0x0 0x0 0x0 0x0

The software shall switch on LED2 and LED0.

For selection 5 (Reset the system):

After selecting this option, the system shall reset and 
after reset it shall display the Main Menu again.

For selection 6 (Stop):

After selecting this option, the system shall do nothing 
and it shall wait for the next options.