Best wifi Arduino

Projects Programming
1

I recently bought and completed some projects with a UNO Rev4
I like the wifi but was kinda disappointed with other features... the real time clock most of all.

Please suggest the best Arduino with wifi.
Thank you

2

What was the problem with that? Was the time not real enough?

Best in what way? Cheapest? Best WiFi range?

3

"Best" is subjective. Many people use ESP32. It has lots of resources and runs the FreeRTOS OS so you can also write muti-tasking applications if you're so inclined.

4

Thank you. I will look into that

5

Wireless data logger, while constantly connected?
Just use NTP (internet time).
That's just a few lines of code with an ESP32, and accurate to a few seconds.

#include <WiFi.h> // ESP32
unsigned long prevTime;
time_t now; // holds epoch
tm tm; // create time structure

void setup() {
  Serial.begin(115200);
  WiFi.begin("SSID", "PW"); // WiFi credentials
  configTzTime("NZST-12NZDT,M9.5.0,M4.1.0/3", "nz.pool.ntp.org"); // https://github.com/nayarsystems/posix_tz_db/blob/master/zones.csv
}

void loop() {
  time(&now);
  if (now != prevTime) { // time has changed?
    prevTime = now; // remember
    localtime_r(&now, &tm); // compute local time
    printf("\n%02u:%02u:%02u", tm.tm_hour, tm.tm_min, tm.tm_sec); // print some of the time elements
  }
}

NTP on the R4 should be the same (no experience with the R4).
Leo..

6

Doesn't the R4 already have an ESP32 on-board?

A bit of Googling suggests that the RTC chip on the R4 is not very accurate. The ESP32 also has one built-in but apparently that is not very accurate either. If all that is needed is a more accurate RTC to track time when the Internet is not connected, then perhaps one option might be to just add a DS3231 module?

When connected to the Internet, using NTP as suggested by Wava is a good choice.

7

The code I posted keeps time within 1-2 seconds between the default 3-hourly automatic NTP updates. Tested on a Seeed XIAO ESP32C3.
Leo..

8

Thank you for the code.
Maybe a better question would be which arduino with wifi do you prefer?
I know … depends on the application

But maybe a preference with a reason why??

9

My current favorite is the Seeed XIAO ESP32C3.

  1. because it's small, and has enough I/O for my needs.
  2. I have a box full of them.
  3. The supplied stick-on aerial has a better range than most modules with a printed or chip aerial.
  4. Simple, I don't mind it's single-core ESP32 (like the ESP8266)
  5. good documentation.
    Leo..
10

Thank you. Perfectly logical and sensible reasons.

11

It also has a LiPo battery option with built-in charger.
Leo..

12

I had a requirement to kept time on an ESP32 when off-line so I wrotes this RTC_NTP_replacement library that makes a DS3231 run like as and NTP client keeping the ESP32 system time in sync with the RTC to within +/-5 ms and ensuring ESP32 system time never goes backwards for consistant timestamps.

The library provides locally served web pages to set the RTC time and the ESP32's time zone for a complete off-line solution.

There is also an option to sync the RTC from NTP if/when internet if available.

User code does not touch the RTC, just uses the usually ESP32 time functions as it would if you were running an NTP client.