Yet another POV (Persistence of Vision) Toy

Preparation with LPC-MT (ARM7)

As there is LCD module in LPC-MT, it is better to remove it to free some gpio pins to drive the LEDs.

The circuit digram:

The completed work:

Coding

When the user move the led line array, you will see a complete pattern.

We have to setup the GPIO output pins for controlling the LEDs (HIGH is OFF, LOW is ON). Please check the tutorial in http://arm.dreamislife.com/

Then we should create the output pattern (in column basis)

        /* Our pattern array */
   	int test_char[] = {
		0x00,0x00,0x82,0xFF,0x82,0x00,
		0x00,0x00,0x08,0x14,0x22,0x42,
		0x00,0x84,0x00,0x42,0x22,0x14,
		0x08,0x00,0x00,0x00,0x7E,0x82,
		0x80,0x80,0x80,0x72,0x7E,0x00,
		0x00,0x00,
		-1,-1,-1,-1,-1
	};
	
	/* the hex array look likes below:
	
	{
	 01234567890123456789012345678901
	 ********************************
	 **111*****11***11*****11***11***
	 ***1*****1***1***1****1*****1***
	 ***1****1*********1***1*****1***
	 ***1*****1*******1****1*****1***
	 ***1******1*****1*****1*****1***
	 ***1*******1***1******1*****1***
	 **111********1*********11111****
	}
	*/

You may want to look at the full source code: view

Afterward, we need to tune the wait time for each column. Such that it fits for your movement in order to display a better picture.

The demo video:

Adding Battery

Lastly, we need to use the 9V battery to power up the LPC-MT, so that we can use it anywhere. A lots of Fun then!!

by senz at dreamislife dot com 2005