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This is actually somewhat more tricky than you would at first thing. First off, the "shock sensor" is merely a spring inside a tube. This will create lots of triggers while it's being "shocked", which really is messy. Secondly, you only want those shocks to make it through to the ESP when you are in deep sleep. Thirdly, you don't want whatever you ...


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Using a static IP address with a gateway is not implemented (as you can see from the source code). To get out to the internet with that library you can only use DHCP (by omitting the WiFi.config(localIp) call).


1

The following may not solve of your problems, but just in case it helps... I was using the ESP8266 both in Station mode and AP. Both worked. In AP mode, it worked but the ESP8266 ignored my instructions to set name and password for the AP , until I realised the following . The password must at least be 8 characters long, otherwise the instruction is ignored ....


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Don't know if you found an answer yet, but I had the exact same issue and eventually came up with this: payload[length] = '\0'; // Add a NULL to the end of the char* to make it a string. int aNumber = atoi((char *)payload); Pretty simple in the end!


1

Once a message has passed through an MQTT broker there is not a way to retrieve it from the broker. Consider instead deciding upon the action at the time the message is received by the subscriber. If this decision needs to be made at a later time consider storing the state in the of the payload of the message on the subscriber. Also consider running Node-...


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The section void loop() { } Is missing in the code, add it and recompile and.....


0

Do NOT try to drive a simple relay from an MMU like a ESP8266, Arduino, or Pi. That would likely destroy the digital pin on the MMU, and might destroy the whole processor. You want a "digital relay module" which has a driver circuit to control the relay, plus some form of isolation to protect the digital pins. A relay like this would be perfect: https://...


1

Voltage is only part of what a relay uses. Check the current requirements for the relay coil/input as well. For example the common result for "3V relay arduino" will produce results for relay MODULEs that contain something akin to a SRD-03VDC-SL-C relay (labeled on the relay itself). Spec for the RELAY (separate search by relay part no) yields a data ...


1

The ESP typically runs on 3.3 Volt, not 3.0 Volt. Secondly, it looks like the board has a voltage regulator, all power goes through the voltage regulator. If that's the case the voltage you need to supply must be lower that the drop-out voltage of the regulator (which is typically around a volt).


1

The SDA line of of ADS1115 will use 3.3 V if you power it with 3.3 V, but then the maximum analog input voltage would be 3.6 V (VDD + 0.3 V). The ACS712 has the middle value at 2,5 V so to read it you need the 5 V range and must power the ADS1115 from 5 V. Then the SDA line of esp8266 will be connected to 5 V logic level, but the esp8266 pins can handle 5 ...


1

The esp8266 is without AT firmware. Even with SoftwareSerial at 115200 baud you should see "ready" from AT firmware and get some response to AT commands. This esp8266 module adapter is simple to flash. It makes the 5 V to 3.3 V conversion for power and RX pin and has a program switch (io 0) and a reset button to put the esp8266 into flashing mode. Use an ...


1

The syntax of six SendHTML you use with true and false is actually wrong. By defining a function like this String SendHTML(uint8_t LED1status,uint8_t BUZZ1status,uint8_t ABA1status), you mean that first, second and third input to this function are Status of LED1, Status of BUZZ1 and Status of ABA1. So try replacing all six SendHTML with true and false ...


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just add this line before every response: server.sendHeader("Access-Control-Allow-Origin", "*");


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12V is the upper limit for input voltage on an Arduino. With a 12V input the regulator has to convert 12-5, or 7 volts, to heat. (That's how linear voltage regulators work.) As the other poster said, Arduinos don't have much heat dissipation on their voltage regulators. Like jksemple, I would suggest powering both the ESP and the Nano from the external ...


1

There seems to be multiple questions in what you are asking. Here I try to answer specifically this one: if I shift a uint16_t (or any non-trivial datatype) right by 8 bits, and mask out the bottom 8 with &0xFF, do I always get the second-least-significant (in this particular case, high) byte, or can the compiler produce alternate outputs based ...


1

Use the 5v regulator to power both the ESP and the Nano. Those onboard regulators have minimal heat dissipation and if they burn out you lose the whole Nano. Check how hot your external regulator gets and mount it on a heat sink if it gets too hot to touch. NB Connect the regulator output to the Nano 5v pin directly


0

Please add the RTC library in the Arduino as below. Open the Library Manager and search for "Rtc by Makuna" and install. You can also checkout the Github page for that particular library at https://github.com/Makuna/Rtc


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No, you have not bricked your ESP8266 by turning on GPIO7's pullup. All that will do is provide a weak pullup on the MISO line of the flash chip, which itself will have no effect - the flash chip's SPI Data Out pin will be able to easily override that weak pullup. You can remove the flash chip and replace it with a completely blank brand new flash chip ...


0

No, your sketch can not brick the device in that way. It's the bootloader that decides after a reset/power-up whether the esp has to accept a firmware (flash button is pressed) or has to run the uploaded sketch. At that point, nothing of your sketch has yet been executed and gpios have their default configuration, which is input anyway. Also, when a pullup ...


2

Well if it doesn't work then it doesn't work so a safe bet is that chip is damaged. I found this document. It states: VBUS pad and jumber can be used to provide 5V to VBUS. By default VBUS is connected to 3.3V; certain USB devices may have issue with this. So I deduce that this is connected directly to 3.3V rail of the chip. Providing 5V without ...


0

for ESP8266 (which your NodeMCU is based upon) , the maximum current is about 20mA sinking and 12mA sourcing per [single] pin. so the maximum current of all GPIOs together is a lot lower than the 500mA USB limits. you have to use external drivers (transistors, MOSFETs) for that purpose. Sink current: the current which is provided when you pull the pin LOW. ...


-1

This is not a big deal... You can do it vary easily, the most simple way is that you can use EEPROM to achieve this.. Simply pass the SSID and PASSWORD of new network to ESP8266 and save it in EEPROM and also create a new variable in eeprom that store the status that new network credentials is entered or not and check it in loop and then fetch new network ...


1

No you can't. Refer to this: https://tttapa.github.io/ESP8266/Chap04%20-%20Microcontroller.html However as that article states there is a dedicated SPI set of pins on the esp8266 so you should be able to use that? From your circuit diagram I see this might not be an option for you as you seem to have most of the pins allocated to a different function. ...


3

No. There is no way you can use it (or not without a lot of messing around...). According to the ESP8266 GPIO Reference Guide: GPIO6 to GPIO11 are usually connected to the flash chip in ESP8266 boards. So, these pins are not recommended to use. If you mess with those pins you won't be able to access the flash chip - and that means that you can't run ...


0

WiFi.begin() in ESP8266WiFi library doesn't wait until the connection completes, it returns immediately. You can check if the connection to WiFi network is established using WiFi.status() as most of the examples show. And it is not mandatory to wait for the connection in setup(). BTW: You can use a separate sketch to set the SSID and password in esp8266 ...


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