LED Matrix Part Four pics

We're nearly there. All the boards are soldered, we just need to connect it all up.

LED Matrix part three more pics 2

LED Matrix part three more pics

LED Matrix part three

Another five boards etched. The circuit is printed onto the transfer sheet on a laser printer. The transfer is then ironed onto a sheet of copper backed board. After sawing into five individual boards we drop it all in the etching fluid for a half hour. The boards then need scrubbing (to remove the ink) and drilling.

We've soldered a bunch of the LEDs to wires in readiness for when we get drilling and soldering tomorrow.

POV part one

Another thing we are looking at is persistence of vision. So far we have a prototype that can display fonts on a line of 8 LEDs. Whats needed is a mechanism to move the LEDs but you can see in the photo that it is working. (For the photo the camera shutter was kept open for two seconds and the camera moved.)

LED Matrix part two

Some code has been written to communicate with our as yet unfinished array of LEDs.
We are not sending a long string of ones and zeros but an integer between 0 and 255 which then controls 8 LEDs. If we send 255 then all eight will turn on. If we send 127 then the first one is off while the next seven are on. What's happening is that the shift registers display binary numbers.

So far we have 64 LEDs being controlled. They're being controlled from one pin on the Arduino via eight shift registers. In the next week or so we should have the remaining 576 LEDs wired up.

To date we have designed the PCBs, etched them, drilled the holes and soldered the components on. We need ten of these boards in total which is a lot of etching, drilling and soldering.

Gareth

LED Matrix

Chris and I are making an LED array which will display two colour images from a webcam. Using 80 shift registers we hope to drive 640 LEDs. With a little help from Jon Bird today, we got to grips with the shift register tutorial on the Arduino website. Its pretty straightforward - the idea is that as new data enters it forces the older data down the pipe so to speak.

In the next week or so I'll write some code to communicate with the Arduino board from a PC sending the image as a string containing 640 characters and post it on here. Until then here's a few pics.

Gareth