Conflict with OneWire?

[sarelvdwalt]

I suspect there is some sort of a conflict with the OneWire library. When I comment out my gpio_viewer.begin(); line (i.e. everything is loaded and set up, but I don't start the viewer) I get the normal 22 degrees or whatever the DS18B20 measures. But, the moment I have that line in the code I get -127. From looking at the OneWire code, that means "Device not connected".

Here is my code for sample:

#include <gpio_viewer.h>
#include <OneWire.h>
#include <DallasTemperature.h>

GPIOViewer gpio_viewer;

// GPIO where the DS18B20 is connected to
const int oneWireBus = 33;

// Setup a oneWire instance to communicate with any OneWire devices
OneWire oneWire(oneWireBus);

// Pass our oneWire reference to Dallas Temperature sensor 
DallasTemperature sensors(&oneWire);

void setup() {
  // Start the Serial Monitor
  Serial.begin(115200);

  // Start the DS18B20 sensor
  sensors.begin();

  // Connect to WiFi:
  gpio_viewer.connectToWifi("REDACTED", "REDACTED");
  gpio_viewer.begin();
}

void loop() {
  sensors.requestTemperatures(); 
  float temperatureC = sensors.getTempCByIndex(0);
  float temperatureF = sensors.getTempFByIndex(0);
  Serial.println(temperatureC);
  delay(1000);
}

Sample output of "normal" operation with it commented out:

21.75
21.75
21.75
21.75
21.75

Sample output of "broken" operation when it is enabled and running:

GPIOViewer >> Connected to WiFi
GPIOViewer >> Release 1.5.6
GPIOViewer >> ESP32 Core Version 3.0.4
GPIOViewer >> Chip Model:ESP32-D0WDQ6, revision:100
GPIOViewer >> No PSRAM
GPIOViewer >> Web Application URL is: http://192.168.107.132:8080
-127.00
GPIOViewer >> Connected, sampling interval is 100ms
-127.00
-127.00
-127.00
-127.00

[thelastoutpostworkshop]

Yes there is probably a conflict, I dot not have a DS18B20, but I will try to find a way to test it.
Can you try with version 1.5 of the GPIOViewer library to see if you get the same results ?

[sarelvdwalt]

Hey hey, ok so I had success. The following versions had a compiler issue:

• 1.5.0
• 1.5.1
• 1.5.2
• 1.5.3

The error was:

In file included from /Users/myname/Documents/Arduino/sarel/sarel.ino:1:
/Users/myname/Documents/Arduino/libraries/GPIOViewer/src/gpio_viewer.h: In member function 'int GPIOViewer::readGPIO(int, uint32_t*, pinTypes*)':
/Users/myname/Documents/Arduino/libraries/GPIOViewer/src/gpio_viewer.h:500:33: error: 'analogGetChannel' was not declared in this scope; did you mean 'analogChannel'?
  500 |         uint8_t analogChannel = analogGetChannel(gpioNum);
      |                                 ^~~~~~~~~~~~~~~~
      |                                 analogChannel

exit status 1

Compilation error: exit status 1

When I tried 1.5.4 it compiled, and upon running it I got a good result:

GPIOViewer >> Connected to WiFi
GPIOViewer >> Release 1.5.4
GPIOViewer >> ESP32 Core Version 3.0.4
GPIOViewer >> Chip Model:ESP32-D0WDQ6, revision:100
GPIOViewer >> No PSRAM
GPIOViewer >> Web Application URL is: http://192.168.107.132:8080
19.00
19.06
19.00
19.06
19.06

Tried version 1.5.5 and that was fine too:

GPIOViewer >> Connected to WiFi
GPIOViewer >> Release 1.5.5
GPIOViewer >> ESP32 Core Version 3.0.4
GPIOViewer >> Chip Model:ESP32-D0WDQ6, revision:100
GPIOViewer >> No PSRAM
GPIOViewer >> Web Application URL is: http://192.168.107.132:8080
19.06
19.06
19.06

So it appears the bug is with 1.5.6 specifically.

[thelastoutpostworkshop]

ok thanks for doing the test, Do you see pin activity on your GPIO 33 (oneWireBus) in the GPIOViewer web application ?

[sarelvdwalt]

Any time :) Yes, I do see activity on it - but only after a while.

• v1.5.5 (where it's working fine) - I see activity immediately, and it's binary (so it shows "High" with a red circle)
• v1.5.6 (where it's broken) - after initial startup it doesn't show anything, and after a while (around a minute later at most) it shows Analog red, value 4095.

[thelastoutpostworkshop]

Thank again it will help. I do not know yet when I will be able to test it, stay tuned!