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  1. M

    8051 program not processing keypad matrix correctly

    I made myself a small PCB (measuring about 6cm by 5cm). This is what is supposed to happen: 1. Upon power-up, the LED goes red to indicate that the unit is ready for input. 2. I then press any key down (where the contacts in the button meet), then the red led goes off. 3. The correct value is...
  2. Lord_Nikon

    Help Please! 8x8 RGB LED Matrix with MAX 7219 and Arduino

    Hello all, I'm in the beginning stages of a project and am just learning how to use an Arduino Uno with a MAX7219 driver with an 8x8 LED RGB Matrix. I'm using someone's source code to just get a basic understanding of how to put all these pieces together and will then modify it as I need to...
  3. atferrari

    Drawing circles - LED matrix

    Given a matrix of LEDs (vertical columns / horizontal rows) I plan to draw circles with extreme LEDs staying from 1 to 8 positions from the center (shown in gray). I came with these 8 distributions and believe they are the best approach to a circle. For eventual reference, consider the start at...

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