Text display program

[shobhabhat]

hi…i’m shobha…i have recently buyed video experimenter and was trying the text dispaly program the link is
http://www.nootropicdesign.com/ve/projects.html

i jsut want only text display on my tv hence edited the program
#include
#include

#define W 136
#define H 96

TVout tv;
unsigned char x,y;
unsigned char originx = 5;
unsigned char originy = 80;
unsigned char plotx = originx;
unsigned char ploty = 40;
char s[32];
unsigned int n = 0;
int index = 0;
int messageLen = 32;
char message[] = “…OVERLAY TEXT AND GRAPHICS ON A VIDEO SIGNAL…OVERLAY TEXT AND GRAPHICS ON A VIDEO SIGNAL”;
char saveChar;

void setup() {
tv.begin(NTSC, W, H);
initOverlay();
tv.select_font(font6x8);
// tv.fill(0);

randomSeed(analogRead(0));
}
// Initialize ATMega registers for video overlay capability.
// Must be called after tv.begin().
void initOverlay() {
TCCR1A = 0;
// Enable timer1. ICES0 is set to 0 for falling edge detection on input capture pin.
TCCR1B = _BV(CS10);

// Enable input capture interrupt
TIMSK1 |= _BV(ICIE1);

// Enable external interrupt INT0 on pin 2 with falling edge.
EIMSK = _BV(INT0);
EICRA = _BV(ISC11);
}

// Required to reset the scan line when the vertical sync occurs
ISR(INT0_vect) {
display.scanLine = 0;
}

void loop() {
saveChar = message[index+22];
message[index+22] = ‘’;

for(int x=6;x>=0;x–) {
if (x<6) {
tv.delay_frame(1);
}
tv.print(x, 87, message+index);

}

message[index+22] = saveChar;
index++;
if (index > 45) {
index = 0;
}

}

ofcourse i’m getting the output but since i’m a very bad programmer i dint understand what exactly is happening inside the void loop() function ????
message[index+22] = ‘’; why this is given null here ???
even in the for loop why x=6??
totally i’m not getting the concept inside void loop() function..
can anybody help me please!!

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