LED Matrix Project Debug, Please Help :[ - Electronic Circuits Projects Diagrams Free

mekohler · 2nd December 2007, 07:03 PM

Been working on an LED matrix table for a few months, with the help of some guy I found online. Here is the circuit schem:

http://www.injektilo.com/Circuit%20P...%20Circuit.jpg

The matrix itself is composed of a 25 cubicles (5 x 5)...each cubicle has 6 LED's in parallel (although the schem shows 8)

http://www.injektilo.com/Circuit%20P...x%20Exampl.jpg

Everything works, but the LED's are not as bright as when I initially tested each cubicle with a 9V battery. You can barely tell when a cubicle is lit through the table's diffusive glass!

Here is the PIC code...in this example I first have the lower leftmost cubicle light up, then all of them...this can be changed to as many patterns and stuff as I want, obviously:

Code:

#include <pic.h>


__CONFIG(INTIO & WDTDIS & PWRTEN & MCLRDIS &
UNPROTECT \
	& UNPROTECT & BORDIS & IESODIS & FCMDIS);

int i, j, k, n, Dlay, CurLetter;

const char Letters[] = {
	
0b10000,
0b00000,
0b00000,
0b00000,
0b00000,

0b11111,
0b11111,
0b11111,
0b11111,
0b11111};

main()
{
	PORTA = 0;			// All Bits are Low
	PORTC = 0b000001;	// Start With Top Left
	CMCON0 = 7;			// Turn Off Comparitors
	ANSEL = 0;			// Turn Off ADC
	TRISA = 0b101000;	// RA5/RA3 Inputs
	TRISC = 0;
	
	CurLetter = 0;		// Start With "A"
	
	while (1 == 1)		// Loop Forever
	{
		for (Dlay = 0; Dlay < 25; Dlay++)
		 for (i = 0; i < 5; i++)
		 {
			 j = Letters[(CurLetter * 5) + i];
			 k = (j >> 2) & 0b010000;
			 PORTC = j & 0b111111;
			 PORTA = k + i;
			 for  (n = 0; n < 259; n++);	// 4ms Delay
		}

	CurLetter = (CurLetter +1) % 2; //Increment Letter

Now I used resistors in the 6 parallel LED's assuming they would get 12V, here are some measurements I made having row 1 and column 1 lit all the time:

Voltage:

1) From PSU Ground to 1 cubicle COLUMN input: 5.25 V

2) From PSU Ground to 1 cubicle ROW input: 3.85 V

3) From ROW input to COLUMN input of a cubicle: .86V (I dont think this means anything, since this is an incorrect way to measure V)

Current:

4) Removing one LED cubicle in the all lit column and connecting column output of LED below and column input of LED above to the meter: 2.53 using 20mA setting/resolution

5) Removing one LED cluster in the all lit row and connecting row ouput of LED to the left and row input of LED to the right to the meter: 12.17 using 20mA setting/resolution

6) Removing the top left LED cubicle and connecting row output from my UNL chip and column output from LED cluster below it: 116 using 200 mA resolution

The guy I am working with says he think the problem lies in the coding...that I am using pulses instead of just on or off states.

I know this is alot of information, but I am all finished, It's just too damn dim!

A video of it not in my table with partitions...it looks brighter in the camera but it's not bright enough to really shine through diffusive glass irl.

http://www.youtube.com/watch?v=kuMaE_b4Wg4

mekohler · 7th December 2007, 05:40 AM

bump :[ :[

Pommie · 7th December 2007, 06:56 AM

From what I can see of your code (you only posted part of it). I would try the following and see if it gets any brighter,

Code:

	while (1 == 1)		// Loop Forever
	{
		//for (Dlay = 0; Dlay < 25; Dlay++)   removed
		 for (i = 0; i < 5; i++)
		 {
			 j = Letters[(CurLetter * 5) + i];
			 k = (j >> 2) & 0b010000;
			PORTA = 7;                      // turn all off
			 PORTC = j & 0b111111;
			 PORTA = k + i;
			 for  (n = 0; n < 259; n++);	// 4ms Delay
			 for  (n = 0; n < 259; n++);	// Do it again
		}

	CurLetter = (CurLetter +1) % 2; //Increment Letter

It would be helpful if you posted all your code.

Mike.

2nd December 2007, 07:03 PM	(permalink)
mekohler New Member	LED Matrix Project Debug, Please Help :[ Been working on an LED matrix table for a few months, with the help of some guy I found online. Here is the circuit schem: http://www.injektilo.com/Circuit%20P...%20Circuit.jpg The matrix itself is composed of a 25 cubicles (5 x 5)...each cubicle has 6 LED's in parallel (although the schem shows 8) http://www.injektilo.com/Circuit%20P...x%20Exampl.jpg Everything works, but the LED's are not as bright as when I initially tested each cubicle with a 9V battery. You can barely tell when a cubicle is lit through the table's diffusive glass! Here is the PIC code...in this example I first have the lower leftmost cubicle light up, then all of them...this can be changed to as many patterns and stuff as I want, obviously: Code: #include <pic.h> __CONFIG(INTIO & WDTDIS & PWRTEN & MCLRDIS & UNPROTECT \ & UNPROTECT & BORDIS & IESODIS & FCMDIS); int i, j, k, n, Dlay, CurLetter; const char Letters[] = { 0b10000, 0b00000, 0b00000, 0b00000, 0b00000, 0b11111, 0b11111, 0b11111, 0b11111, 0b11111}; main() { PORTA = 0; // All Bits are Low PORTC = 0b000001; // Start With Top Left CMCON0 = 7; // Turn Off Comparitors ANSEL = 0; // Turn Off ADC TRISA = 0b101000; // RA5/RA3 Inputs TRISC = 0; CurLetter = 0; // Start With "A" while (1 == 1) // Loop Forever { for (Dlay = 0; Dlay < 25; Dlay++) for (i = 0; i < 5; i++) { j = Letters[(CurLetter * 5) + i]; k = (j >> 2) & 0b010000; PORTC = j & 0b111111; PORTA = k + i; for (n = 0; n < 259; n++); // 4ms Delay } CurLetter = (CurLetter +1) % 2; //Increment Letter Now I used resistors in the 6 parallel LED's assuming they would get 12V, here are some measurements I made having row 1 and column 1 lit all the time: Voltage: 1) From PSU Ground to 1 cubicle COLUMN input: 5.25 V 2) From PSU Ground to 1 cubicle ROW input: 3.85 V 3) From ROW input to COLUMN input of a cubicle: .86V (I dont think this means anything, since this is an incorrect way to measure V) Current: 4) Removing one LED cubicle in the all lit column and connecting column output of LED below and column input of LED above to the meter: 2.53 using 20mA setting/resolution 5) Removing one LED cluster in the all lit row and connecting row ouput of LED to the left and row input of LED to the right to the meter: 12.17 using 20mA setting/resolution 6) Removing the top left LED cubicle and connecting row output from my UNL chip and column output from LED cluster below it: 116 using 200 mA resolution The guy I am working with says he think the problem lies in the coding...that I am using pulses instead of just on or off states. I know this is alot of information, but I am all finished, It's just too damn dim! A video of it not in my table with partitions...it looks brighter in the camera but it's not bright enough to really shine through diffusive glass irl. http://www.youtube.com/watch?v=kuMaE_b4Wg4

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7th December 2007, 05:40 AM	(permalink)
mekohler New Member	bump :[ :[