Arduino mega and nodemcu esp2866-esp12e connect together for wifi

Projects General Guidance
1

Hi

I have a dev nodemcu-esp12e and a mega. I also have a esp-01 but thats in use elsewhere.

what i am trying to do is use the esp as a wifi AP for the mega. Currently the esp is just got a dht22 on it to get temp and humidity from a hydro tent.

I have a mega that is monitoring EC and water temps. I also have home assistant running.

what i want to do is add the dht to the mega and use the esp to do the wifi thing ( i would use the esp but need 5 analog pins.. ) to send mqtt back to home assistant.

IS there anyway to do this? I don't really want to use AT commands if i can avoid it (been WAY to many years since ive had to use At)

would the easier approach be just to get a wifi shield (but that uses the esp12e chip as well and it might stuff up my LCD shield though i prob wont need that if i can wifi)

Hope I made sense :slight_smile:

any help on this would be great. Its the esp DEV board

thanks in advance

2

You can program the ESP with the Arduino IDE using the Arduino Esp core. Use one of the serial ports to communicate between the Mega and ESP.

3

yeah i have had the esp01 working in the past but wondering if i can call any headers to control the esp via the mega.. eg wifi.begin() etc or is the only way to use AT commands.

Currently the esp has been used with arduino IDE so i assume I would need to reflash the device with the right firmware,,

Basically trying to decide if its worth getting a shield (that uses the esp12e chip anyway!) or work it out myself... or if i can use the megas analog pin and work out how to send that data over tx1/rx1 to the esp and then send that info to the mqtt broker (if you follow)

other option is to use multiplexing on the esp but unsure if it would work with my homemade probe and dallas onewire temp sensor

4

worked it out. i was overthinking it all. the dev board esp12e is just a breakout board for the esp12e chip. I was treating it differently. issue sorted :slight_smile:

5

There are a few ways to solve your issues.

  1. the AT command set.
  2. program the ESP8266 as independent web server, and read the data from the Mega using Serial or I2C communications.
  3. get an I2C ADC port expander like the ADS1115 and connect everything to the ESP8266 (that way you have the five analog ports you want: four on the ADS1115, one on the ESP8266 - but mind the ESP8266s ADC range is 0-1V), freeing up your Mega for another project.