POV poster copy.jpg

The colorful Persistence Of Vision (POV) kit enables you to create colorful messages in air with just 8 LEDs. This kit is great introduction to soldering and AVR/Arduino Programming. The kit does not require a external programmer, it is self programmable with USB.

Solder it!

  • Image above shows the layout of various components for the board. It is also printed on the PCB.

Component Layout

The image shows reference numbers for all the components.

  • From the table below find out the exact part for the reference number.

Component List

ref
value
Item count
C1
4.7uF
1
C2
100nF
1
C3,C4
22pF
2
CON1
AVR-ISP-10
1
D1,D2
3.6V Zener
2
IC1
ATMEGA8-P
1
J1
USB_2
1
LED1..LED8
LED-RGB
8
P8
Batt
1
Q1..Q3
BC547
3
R1
2.2K
1
R2,R3
68E
2
R4
10K
1
R5..R12
22
8
R13..R15
1K
3
SW1
Boot
1
SW2
Reset
1
X1
12MHz
1

Programming

C Code


#include <avr/io.h>
#include<util/delay.h>
#include<stdint.h>
#include<avr/interrupt.h>
 
#define Blue 3
#define Green 4
#define Red 5
 
uint8_t i=0;  
 
 
const static uint16_t image[]= 
{
{
0b0000100011111111, 0b0000100011111111, 0b0000100011111111, 0b0000100011111111,
0b0000100011111111, 0b0000100011111111, 0b0000100011111111, 0b0000000000000000,
0b0000010011111110, 0b0000010000010001, 0b0000010000010001, 0b0000010000010001,
0b0000010011100001, 0b0000000000000000, 0b0000010001111110, 0b0000010010010001, 
0b0000010010010001, 0b0000010010010001, 0b0000010000001110, 0b0000000000000000, 
0b0000001011111111, 0b0000001000010001, 0b0000001000010001, 0b0000001000010001, 
0b0000001000001110, 0b0000000000000000, 0b0000001000001110, 0b0000001000010001, 
0b0000001000010001, 0b0000001011111111, 0b0000000000000000, 0b0000000000000000,
0b0000100001110000, 0b0000100011111100, 0b0000100011111110, 0b0000100011111111,
0b0000100011111111, 0b0000100011111110, 0b0000100011111100, 0b0000100001111000, 
0b0000000000000000, 0b0000000000000000, 0b0000010011111110, 0b0000010000010001, 
0b0000010000010001, 0b0000010000010001, 0b0000010011100001, 0b0000000000000000,
0b0000001001110000, 0b0000001010001000, 0b0000001010001000, 0b0000001010001000,
0b0000001011111111, 0b0000000000000000, 0b0000001001110000, 0b0000001010001000, 
0b0000001010001000, 0b0000001010001000, 0b0000001011111111, 0b0000000000000000,
0b0000010001111110, 0b0000010010010001, 0b0000010010010001, 0b0000010010010001,
0b0000010010001111, 0b0000000000000000, 0b0000000000000000, 0b0000010011111111, 
0b0000010000010000, 0b0000010000010000, 0b0000010000010000, 0b0000010011111111 
};
 
void disp(uint16_t);
 
ISR (TIMER1_OVF_vect)    // Timer1 ISR
{
	disp(image[i]);
	i++;
 
	if(i==72)
	i=0;
 
	TCNT1H=0xFF;    // Reload the 16-bit count value
	TCNT1L=0xF0;    // in timer1 count registers
}
 
 
int main(void)
{	
    DDRC = 0b11111111;
	DDRD = 0b11111111;
 
	PORTC = 0b11111111;
	PORTD = 0b00000111;
 
	TCNT1H=0xFF;   // Load the 16-bit count value
	TCNT1L=0xF0;   // for 1 sec at 7.3728MHz
 
	TCCR1A=0x00;
	TCCR1B=0x05;  // Timer mode with 1024 prescAler
	TIMSK=0x04;   // Enable timer1 overflow interrupt(TOIE1)
	sei();        // Enable global interrupts by setting global interrupt enable bit in SREG
 
    while(1)
    {
 
    }
}
 
void disp(uint16_t pat)
{
 
	PORTC = pat & 0x3f;
	PORTD = (pat>>6)& 0xff;
}


Arduino Code

Arduino Code will be uploaded soon.

Pattern Generation

To create an image/patterm, you can use the POV image maker application. Maker.PNG

Uploading the Pattern

  • Install USBasp driver on your computer. Note that the it will show up as not recognized if the reset sequence is not followed

Reset Sequence for uploading new pattern/image

POV Reset Sequence for uploading new image
  • Perform reset sequence every time you connect the kit to the computer.
  • To upload a new image, hold down the RESET button, press and release the BOOT button and then release the RESET button as shown below.
  • Note the LEDS will stop blinking once the kit is detected by the computer.

Downloads