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  1. Lord_Nikon

    Voltage Levels

    So, I decided to start an 8x8 LED matrix project using a MAX7219 and PIC18F4550. My issue I've run into is that my the LED matrix I found is a max 2.7 forward voltage drop. The MAX7219 outputs around V+ -1.The minimum amount for V+ is 4V so this will put me near the 2.7V maximum of the matrix...
  2. A

    Inverted PWM using PIC18F4550

    Hi everyone. My project requires to send PWM signal to the MOSFET. I am using 6N137 Optocoupler. The output of this is inverted signal. One way is to use an inverting IC at the output of PWM pin of micrcontroller PIC18F4550. This got me thinking is there a way I can send inverted PWM signal to...
  3. GraffZeppelin

    DS18B20 > OneWire > PIC18F4550 > code query

    Hello all, In the last three days I was struggling to read temperature data from a single DS18B20 when using non-parasitic OneWire protocol and a PIC18F4550. Finally I had a break-trough (at least I think I have), when I decided to take baby steps and : 1. Read a presence pulse; 2. Read device...

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