How to make ESP running Blynk to get data from Arduino

Please give me some code and wiring examples for how to make ESP-01 running Blynk to get data from Arduino.

My ESP-01 is gathering temperature sensor data and sending it to Blynk cloud - working fine. My Arduino Uno is gathering energy pulse sensor data.

This sensor data needs to be available to ESP in order to send it forward to Blynk cloud.
ESP and Arduino can be physically connected to each other for example using Softwareserial or any other way. No wireless connection between those is needed.

This is my problem: How to make ESP to read data from Arduino? Code and wiring examples are welcome - but please don’t forget to tell me which code is for ESP and which is for Arduino :wink:

Well now you may wonder why I don’t read energy pulse sensor data directly using ESP. That’s because I have not managed to get correct data results using ESP:s interrupts. Arduino is doing this job just fine!

Please look through the already existing Documentation, Help Center and Example Sketches… links all at the top of this page.

The ESP as shield just turns the ESP-01 into a WiFi to serial adapter (using the AT firmware)… you don’t program the ESP in that case, you only program the Arduino…

ESP standalone works independently from the Arduino, in which case you program the ESP as you have done…

There are also various (non Blynk related - no support here) ways to also share connections between different MCU’s like this…

But you will not have enough pins on the ESP-01 to make it worthwhile… So just use it as shield or standalone, one or other.

@Gunner Thank you for helping me to solve my problem. Although my case is not purely Blynk related, it’s nice to have quick and professional help from community gurus like you!

Your suggestion one - using ESP as a WiFi shield for Arduino. Well - this is what I’ve been trying to avoid as long as possible. I have some experience working with that configuration and found it unstable and difficult to build and program.

Your suggestion two - using ESP as standalone. That’s what I am using to measure temperatures etc. and sending them to Blynk app. Works fine so far. Problem comes with pulse sensors which require special things at the software (interrupts handling etc) and hardware (pull-up resistors etc) side. Tried hard - but couldn’t get ESP working reliable enough.

My goal is to use Arduino to do all the pulse sensor things (works fine!) and use it to serve energy data to ESP, which in turn does all things with Blynk. This may be done by wiring MCU:s together using serial connection (TX from Arduino to RX at ESP). That’s all at the hardware side! On software side must be some kind of handshaking between those two - I guess - but how?

Google i2c master and slave :slight_smile:

This is all handled by that Easy Transfer library I provided the link to above… Serial or i2C options from what I can gather. For more details of how… well, that is a question for that libraries author.