I've built a simple LED sequencer using PIC 18f4550. Outputs are 10 pins on ports C&D. I have now built (soldered) this circuit 3 times and it still only powers on intermittently. I installed a very low current "power on" LED to help troubleshoot. I notice if I touch the chip or certain areas of the board, the circuit works (& power light on). But it intermittently goes out. Almost like there's a loose connection or some capacitive issue. Circuit works fine when the power light is on. Symptoms are the same whether breadboard or soldered. Ideas?
Thanks
please excuse the crudeness of this drawing.
Answer
You probably are missing a pullup on the reset pin (/MCLR)
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