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If you supply the entire circuit board with a 3V AC/DC supply, it makes no sens to replace the 3V supply for a 5V supply + 3V LDO. However if other components on this board use 5V, then you must provide 3V to the components which don't support a higher voltage. Then use a LDO. A LDO is a voltage regulator. There are LDO and non-LDO regulators. LDO only ...


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This is a simple circuit for ESP8266 chip and can be modified more, First of all let's answer your questions: 1- 10K is a normal pull resistor for designers, but if your system is very sensitive on current drawn, or your system is battery powered, it's better to increase pull-up resistor to reduce power consumption while key pressed or I2C transmission. 2- ...


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I have checked some info on the ESP8266-01, and your problem is that BOTH the GPIO and GPIO2 need to be pulled UP for the chip to start working. The GPIO2 in your case is pulled DOWN through the base of the transistor. The chip at startup checks the GPIO pins, and then it makes them available for use as inputs and outputs. That's why your chip works without ...


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One problem that I can see with your circuit is that the 2N2222 transistor may not have sufficient current gain to turn the relay on (and keep it on). The relay may need anywhere from 60 to 100mA, the transistor gain is guaranteed around 50 at around 100mA AND (this is VERY important) 1.0V across the collector-emitter junction. This means that you might ...


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The Tasmota firmware uses the esp8266 Arduino core. The Wire library in esp8266 Arduino uses software I2C. It can use any pair of suitable io pins. Default pins for most esp8266 variants are SDA 4 and SCL 5.


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All I did was Google the ESP-12F and the first result was THIS. On page 14 it tells you the I2C pins needed. Go up to page 8/9 for the pinout description.


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Standard RS-232 uses both positive and negative voltages, usually in the ballpark of +/- 10V. Because generating high voltages and negative voltages requires some extra circuitry, a lot of devices today use the RS-232 signaling with standard logic levels instead, like the 0V/+3.3V of your ESP8266. Since you're measuring +10V from your sensor, that suggests ...


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That’s the hard way, and it will have flicker artifacts if the PWM rate is too low. The easy way is to use WS2812 -interfaced RGB LEDs which come singly or in strips. WS2812 protocol allows daisy-chain connection of multiple LEDs.


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The question I have as per the schematic note is - which 9V regulator would I use , given I need around 600mA from it ... You don't really need a regulator! LEDs are very sensitive to voltage but with the current limiting resistors you have correctly applied to each LED the variation in current and brightness will be quite acceptable for a reasonable ...


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To control your LED brightness, you should pulse-width (PWM) modulate your LEDs at a rate faster than the human eye can see. Modern MCUs often have built-in PWM circuits. If not, they will always have timers, and you can use timers and interrupts to do it with minimal software. https://randomnerdtutorials.com/esp8266-pwm-arduino-ide/ Many different sizes ...


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Why don't you just do everything on the ESP? There's no reason to use the AT interface and add a second microcontroller. Having said that, I wonder how information gets into your MCU in a way that doesn't make it accessible to an adversary.


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