Max Feeds per Group AIO Arduino
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Max Feeds per Group AIO Arduino

by Weather411 on Sat Nov 21, 2020 12:41 pm

Scoured the forum and I don't see this issue previously addressed. I've tried the same code on ESP8266 and ESP32, both show board stack errors/board resets in the Serial Monitor when I write data to more than 7 feeds to 1 group at one time. When I write data to 6 feeds (or less) to 1 group at one time, there are no stack errors/board resets. Was a weather station with many variables coming back, now simplified program to random number generator to troubleshoot.

Adafruit IO Arduino v4.0.1
ESP8266 Board v2.7.4
ESP32 Board v1.0.4

Code: Select all | TOGGLE FULL SIZE
 * A simple random number generator to test max number of feeds per group (written at once)

/************************** Configuration ***********************************/

//edit the config.h tab and enter your Adafruit IO credentials (including WiFi, cellular or ethernet)
#include "config.h"

//set baud rate and delays
  unsigned long baud_rate = 115200;   //default value for all sketches
  unsigned long refresh_rate = 30000; //number of milliseconds between readings

//for WiFi connection
  const float txPwr = 20.5;               //transmit signal strength in dBm, max = 20.5, min = 0.0
  unsigned long WiFi_retryTime = 20000;   //number of ms to establish WiFi connection, otherwise terminate program (or force deep sleep in ver2)

//set up the group
  AdafruitIO_Group *group = io.group("Test_1");

//set up feed names (format needs to be const char *<variable> = "{FeedName}")
  const char *rn_a = "Random_Num_a";
  const char *rn_b = "Random_Num_b";
  const char *rn_c = "Random_Num_c";
  const char *rn_d = "Random_Num_d";
  const char *rn_e = "Random_Num_e";
  const char *rn_f = "Random_Num_f";
  const char *rn_g = "Random_Num_g";
  const char *rn_h = "Random_Num_h";
  const char *rn_i = "Random_Num_i";
//  const char *rn_j = "Random_Num_j";
//  const char *rn_k = "Random_Num_k";
//  const char *rn_l = "Random_Num_l";

void setup() {


  /************ CAPTURE START SETUP TIME (MS) ************/
  Serial.println(); Serial.println();
  Serial.print("Millis SETUP (start) = "); Serial.println(millis());

  /************ CONNECT TO ADAFRUIT IO LIBRARY ************/


void loop() {

  /************ SETUP AND WRITE TO ALL FEEDS ************/ 

  /************ DELAY BETWEEN FEED WRITES ************/     

void connect_AIO() {
  Serial.println("Connecting to WiFi and Adafruit IO...");
  WiFi.persistent(false);  //will only change in-memory WiFi and does *not* affect the WiFi settings stored in Flash memory (saves having to rewrite Flash each "loop")
  WiFi.mode(WIFI_STA);  //can be WIFI_AP, WIFI_STA, WIFI_AP_STA, or WIFI_OFF. Setting as STA will save battery.
  unsigned long wifiConnectStart = millis();
  while (io.status() < AIO_CONNECTED) {
    Serial.print('.'); delay(200);  //draw dots every 200ms while attempting to connect to WiFi
    if (millis() - wifiConnectStart >= WiFi_retryTime) {
      Serial.println("Failed to connect to WiFi!!!");

    Serial.println(); Serial.println("WiFi connected!!");
    Serial.print("IP address: "); Serial.println(WiFi.localIP());

void feed_write_AIO() {
  Serial.println("Setting up and writing data to Adafruit IO feeds...");
  // io.run(); is required for all sketches
  // it should always be present at the top of your loop function
  // it keeps the client connected to io.adafruit.com, and processes any incoming data

/*********** GET RANDOM NUMBER VALUES ***********/
  int random_num_1 = random(1, 21);
  int random_num_2 = random(22, 41);
  int random_num_3 = random(42, 61);
  int random_num_4 = random(62, 81);
  int random_num_5 = random(82, 101);
  int random_num_6 = random(102, 121);
  int random_num_7 = random(122, 141);
  int random_num_8 = random(142, 161);
  int random_num_9 = random(162, 181);
//  int random_num_10 = random(182, 201);
//  int random_num_11 = random(202, 221);
//  int random_num_12 = random(222, 241); 

/*********** SERIAL PRINT VALUES ***********/   
  Serial.print("Random Number 01: "); Serial.print(random_num_1); Serial.println();
  Serial.print("Random Number 02: "); Serial.print(random_num_2); Serial.println();
  Serial.print("Random Number 03: "); Serial.print(random_num_3); Serial.println();
  Serial.print("Random Number 04: "); Serial.print(random_num_4); Serial.println();
  Serial.print("Random Number 05: "); Serial.print(random_num_5); Serial.println();
  Serial.print("Random Number 06: "); Serial.print(random_num_6); Serial.println();
  Serial.print("Random Number 07: "); Serial.print(random_num_7); Serial.println();
  Serial.print("Random Number 08: "); Serial.print(random_num_8); Serial.println();
  Serial.print("Random Number 09: "); Serial.print(random_num_9); Serial.println();
//  Serial.print("Random Number 10: "); Serial.print(random_num_10); Serial.println();
//  Serial.print("Random Number 11: "); Serial.print(random_num_11); Serial.println();
//  Serial.print("Random Number 12: "); Serial.print(random_num_12); Serial.println();

/******** FORMAT group->set("{FEED NAME VARIABLE}", {VALUE}) ********/
  group->set(rn_a, random_num_1);
  group->set(rn_b, random_num_2);
  group->set(rn_c, random_num_3);
  group->set(rn_d, random_num_4);
  group->set(rn_e, random_num_5);
  group->set(rn_f, random_num_6);
  group->set(rn_g, random_num_7);
  group->set(rn_h, random_num_8);
  group->set(rn_i, random_num_9);
//  group->set(rn_j, random_num_10);
//  group->set(rn_k, random_num_11);
//  group->set(rn_l, random_num_12);

  Serial.println("All group feed data set completed");

/*********** SAVE TO ADAFRUIT IO ***********/

  Serial.println("All group feed data SAVED");

/**************** TERMINATES PROGRAM VIA INFINITE LOOP ****************/
void stopSketch()
     while(true) {}

This program makes it easy to troubleshoot since I just have to comment/uncomment a few lines to add or decrease number of feeds writing to the one group ("Test_1").

When I decode my stack error, I get this:

Code: Select all | TOGGLE FULL SIZE
Exception 28: LoadProhibited: A load referenced a page mapped with an attribute that does not permit loads
PC: 0x4000bf80
EXCVADDR: 0x00b98e28

Decoding stack results
0x4020201d: Adafruit_MQTT::readSubscription(short) at C:\Users\Mike\Documents\Arduino\Sketches\1_Testing\libraries\Adafruit_MQTT\Adafruit_MQTT.cpp line 460
0x40100274: millis() at C:\Users\Mike\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.7.4\cores\esp8266\core_esp8266_wiring.cpp line 188
0x402053c4: BearSSL::WiFiClientSecure::available() at C:\Users\Mike\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.7.4\libraries\ESP8266WiFi\src\WiFiClientSecureBearSSL.cpp line 394
0x4020215c: Adafruit_MQTT::processPackets(short) at C:\Users\Mike\Documents\Arduino\Sketches\1_Testing\libraries\Adafruit_MQTT\Adafruit_MQTT.cpp line 418
0x40209238: Adafruit_MQTT_Client::connected() at C:\Users\Mike\Documents\Arduino\Sketches\1_Testing\libraries\Adafruit_MQTT\Adafruit_MQTT_Client.cpp line 48
0x40201739: AdafruitIO::run(unsigned short, bool) at C:\Users\Mike\Documents\Arduino\Sketches\1_Testing\libraries\Adafruit_IO_Arduino\src\AdafruitIO.cpp line 342
0x40206b34: Print::println() at C:\Users\Mike\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.7.4\cores\esp8266\Print.cpp line 186
0x402011c6: feed_write_AIO() at C:\Users\Mike\Desktop\Temp\Arduino\AIO\AIO_RandomNumber_MaxFeedTest_Forum/AIO_RandomNumber_MaxFeedTest_Forum.ino line 94
0x402074a8: __esp_yield() at C:\Users\Mike\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.7.4\cores\esp8266\core_esp8266_main.cpp line 119
0x40201360: loop() at C:\Users\Mike\Desktop\Temp\Arduino\AIO\AIO_RandomNumber_MaxFeedTest_Forum/AIO_RandomNumber_MaxFeedTest_Forum.ino line 57
0x402075c0: loop_wrapper() at C:\Users\Mike\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.7.4\cores\esp8266\core_esp8266_main.cpp line 197

I really want to be able to code more than 7 feeds to one group at once. I did test another version of this program where feed data is split amongst multiple groups, and in that case, I can send more than 7 feeds (just not ideal for my needs). This will significantly impact how I'm going to code my next project so any and all help is greatly appreciated - thanks in advance!

Posts: 12
Joined: Fri Sep 15, 2017 7:38 pm

Re: Max Feeds per Group AIO Arduino

by GubTerra on Sun Nov 22, 2020 1:44 am

im having the same issue... so if i want to control more than 7 states i need to cut it in diferent groups?

Posts: 9
Joined: Wed Nov 04, 2020 10:48 am

Re: Max Feeds per Group AIO Arduino

by brubell on Mon Nov 23, 2020 10:20 am

Could you please file this as an issue on the Adafruit IO Arduino repository directly: https://github.com/adafruit/Adafruit_IO_Arduino/issues


Posts: 1417
Joined: Fri Jul 17, 2015 10:33 pm

Re: Max Feeds per Group AIO Arduino

by Weather411 on Mon Nov 23, 2020 3:46 pm

Done, thank you!

Posts: 12
Joined: Fri Sep 15, 2017 7:38 pm

Re: Max Feeds per Group AIO Arduino

by Weather411 on Tue Dec 22, 2020 9:03 am

Hello again,

Is the Arduino Adafruit IO library still being supported by Adafruit? Been a month and I haven't noticed any activity on Github. I would rather continue to use the library than re-write all my code to make manual HTTP requests.

Thanks in advance

Posts: 12
Joined: Fri Sep 15, 2017 7:38 pm

Please be positive and constructive with your questions and comments.