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Finally closed my Facebook account.  😿

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Pboard

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Pboard  Project Pboard (short for "P-channel board") is the working nickname of a new driver board that I plan to use with the next version RLbC.  Whereas RLbC 2 only featured output relays, Pboard will make use of  Adafruit's PCA9853 based servo-driver board to provide PWM signals to the outputs via P-channel MOSFETS.  Doing so will allow for fading the lights. Why use P-channel Mosfets? I chose to use  FQP27P06 P-channel MOSFETS over the more commonly accepted easier to wire N-channel logic-level MOSFETS out there simply because I wanted high-side switching.  Call me weird or old-fashioned, but I have always designed my low-level voltage systems with Common tied to the "negative" side of a supply (split or dual-tap not withstanding). However, going to P-channel switching does make the design a little more complex. Buffering is required since I can not directly tie the output of a PCA9685 to Vss (12VDC) otherwise it will be damaged.   Invert
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RESET circuit

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One thing I had to add was a power-up RESET circuit, which is just a 10uF cap and 1K resistor in series across the 5v supply. The RESET pin on the counters are connected to where the resistor and cap meet so that at power up, the cap is effectively a short to 5+. This causes a logic HI on the RESET lines to set the counters to zero. After the capacitor has charged up, it no longer looks like a short to 5+, so the only path left is through the resistor back to ground. That presents a logic LOW on the RESET pin, which allows the counter to count up or down.
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Simple non-inverting 3.3v output to 5V When the input signal is high, the transistor is effectively off, so the output is fed 5V  via resistor R2. When the input signal is low, the transistor conducts, pulling the output low as well.
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