ESP32 I2C randomly stops working

[Fazeli24]

I've been trying to get 2 TCS34725 Color sensors to work, these pcb to be exact: https://www.az-delivery.de/en/products/ ... d_source=1

I use a ESP32 Node MCU I bought here: https://www.berrybase.de/esp32-nodemcu- ... d_source=1
My problem is, that the I2C connection is very unreliable. I'm using 4.7k ohm PullUps on both SDA and SCL. I also use the Adafruit TCS34725 library. Because I can't change the sensor I2C adress, I use two i2c buses on the ESP32. But my problem is that it doesn't recognise the sensors when I initialise both of them at the same time. It also only works sometimes when I use only one sensor, and don't initialise the second. I checked all the sensors and connections multiple times, but can't find the issue. The SDA and SCL cables are ~15cm each.

Here is part of my code:

Code: [Select all] [Expand/Collapse]

1. Adafruit_TCS34725 leftColorSensor = Adafruit_TCS34725(TCS34725_INTEGRATIONTIME_180MS, TCS34725_GAIN_16X);
2. TwoWire i2c_left = TwoWire(0);
3. Adafruit_TCS34725 rightColorSensor = Adafruit_TCS34725(TCS34725_INTEGRATIONTIME_180MS, TCS34725_GAIN_16X);
4. TwoWire i2c_right = TwoWire(1);
5.  
6. int blackThreshold = 300;
7.  
8. void setup() {
9.   Serial.begin(115200);
10.   pinMode(15, INPUT);
11.   pinMode(14, INPUT);
12.   pinMode(34, INPUT);
13.   pinMode(33, INPUT);
14.   pinMode(27, INPUT);
15.  
16.  
17.   i2c_left.begin(21, 22, 100000);
18.   i2c_right.begin(25, 13, 100000);
19.   delay(500);
20.   if (leftColorSensor.begin(0x29, &i2c_left)) {
21.     Serial.println("Found sensor");
22.   } else {
23.     Serial.println("No TCS34725 found ... check your connections");
24.     while (1);
25.   }
26.  
27.   if (rightColorSensor.begin(0x29, &i2c_right)) {
28.     Serial.println("Found sensor");
29.   } else {
30.     Serial.println("No TCS34725 found ... check your connections");
31.     while (1);
32.   }

GeSHi © Codebox Plus Extension

[horace99]

try running https://wokwi.com/projects/350122233155289684 which scans Wire and Wire1 for I2C devices

[horace99]

I have one TCS34725 so could not carry out full test but running the following on an ESP32

Code: [Select all] [Expand/Collapse]

1. #include <Wire.h>
2. #include "Adafruit_TCS34725.h"
3.  
4. Adafruit_TCS34725 leftColorSensor = Adafruit_TCS34725(TCS34725_INTEGRATIONTIME_180MS, TCS34725_GAIN_16X);
5. TwoWire i2c_left = TwoWire(0);
6. Adafruit_TCS34725 rightColorSensor = Adafruit_TCS34725(TCS34725_INTEGRATIONTIME_180MS, TCS34725_GAIN_16X);
7. TwoWire i2c_right = TwoWire(1);
8.  
9. int blackThreshold = 300;
10.  
11. boolean leftOK = true, rightOK = true;
12. void setup() {
13.   Serial.begin(115200);
14.   pinMode(15, INPUT);
15.   pinMode(14, INPUT);
16.   pinMode(34, INPUT);
17.   pinMode(33, INPUT);
18.   pinMode(27, INPUT);
19.  
20.  
21.   i2c_left.begin(21, 22, 100000);
22.   i2c_right.begin(25, 13, 100000);
23.   delay(500);
24.   if (leftColorSensor.begin(0x29, &i2c_left)) {
25.     Serial.println("Found left sensor");
26.   } else {
27.     Serial.println("No left TCS34725 found ... check your connections");
28.     leftOK = false;  //while (1);
29.   }
30.  
31.   if (rightColorSensor.begin(0x29, &i2c_right)) {
32.     Serial.println("Found right sensor");
33.   } else {
34.     Serial.println("No right TCS34725 found ... check your connections");
35.     rightOK = false;  //while (1);
36.   }
37. }
38.  
39. void loop(void) {
40.   uint16_t r, g, b, c, colorTemp, lux;
41.   if (leftOK) {
42.     leftColorSensor.getRawData(&r, &g, &b, &c);
43.     // colorTemp = tcs.calculateColorTemperature(r, g, b);
44.     colorTemp = leftColorSensor.calculateColorTemperature_dn40(r, g, b, c);
45.     lux = leftColorSensor.calculateLux(r, g, b);
46.  
47.     Serial.print("left Color Temp: ");
48.     Serial.print(colorTemp, DEC);
49.     Serial.print(" K - ");
50.     Serial.print("Lux: ");
51.     Serial.print(lux, DEC);
52.     Serial.print(" - ");
53.     Serial.print("R: ");
54.     Serial.print(r, DEC);
55.     Serial.print(" ");
56.     Serial.print("G: ");
57.     Serial.print(g, DEC);
58.     Serial.print(" ");
59.     Serial.print("B: ");
60.     Serial.print(b, DEC);
61.     Serial.print(" ");
62.     Serial.print("C: ");
63.     Serial.print(c, DEC);
64.     Serial.print(" ");
65.     Serial.println(" ");
66.   }
67.   if (rightOK) {
68.     rightColorSensor.getRawData(&r, &g, &b, &c);
69.     // colorTemp = tcs.calculateColorTemperature(r, g, b);
70.     colorTemp = rightColorSensor.calculateColorTemperature_dn40(r, g, b, c);
71.     lux = rightColorSensor.calculateLux(r, g, b);
72.  
73.     Serial.print("right Color Temp: ");
74.     Serial.print(colorTemp, DEC);
75.     Serial.print(" K - ");
76.     Serial.print("Lux: ");
77.     Serial.print(lux, DEC);
78.     Serial.print(" - ");
79.     Serial.print("R: ");
80.     Serial.print(r, DEC);
81.     Serial.print(" ");
82.     Serial.print("G: ");
83.     Serial.print(g, DEC);
84.     Serial.print(" ");
85.     Serial.print("B: ");
86.     Serial.print(b, DEC);
87.     Serial.print(" ");
88.     Serial.print("C: ");
89.     Serial.print(c, DEC);
90.     Serial.print(" ");
91.     Serial.println(" ");
92.   }
93. }

GeSHi © Codebox Plus Extension

TCS34725 connected to GPIO21 SDA and GPIO22 SCL (VCC to 3.3V) gave

Code: Select all

Found left sensor
No right TCS34725 found ... check your connections
left Color Temp: 3918 K - Lux: 390 - R: 642 G: 613 B: 503 C: 1300  
left Color Temp: 4162 K - Lux: 432 - R: 712 G: 693 B: 588 C: 1478  
left Color Temp: 4186 K - Lux: 448 - R: 743 G: 723 B: 617 C: 1543  
left Color Temp: 4141 K - Lux: 464 - R: 782 G: 753 B: 643 C: 1613  
left Color Temp: 4051 K - Lux: 431 - R: 714 G: 685 B: 571 C: 1490  
left Color Temp: 4033 K - Lux: 462 - R: 737 G: 707 B: 566 C: 1652  
left Color Temp: 4309 K - Lux: 1068 - R: 1632 G: 1610 B: 1288 C: 4206  
left Color Temp: 5038 K - Lux: 3917 - R: 4604 G: 5473 B: 4408 C: 14530  
left Color Temp: 5608 K - Lux: 7580 - R: 7718 G: 10352 B: 8544 C: 27312  
left Color Temp: 5590 K - Lux: 8622 - R: 8078 G: 11253 B: 8903 C: 28630  
left Color Temp: 4747 K - Lux: 10936 - R: 13057 G: 14949 B: 11503 C: 40660  
left Color Temp: 4523 K - Lux: 8350 - R: 11376 G: 11967 B: 9352 C: 34216  
left Color Temp: 3918 K - Lux: 4549 - R: 9195 G: 7603 B: 6101 C: 24387  
left Color Temp: 3366 K - Lux: 2732 - R: 8317 G: 5442 B: 4313 C: 18840  
left Color Temp: 3937 K - Lux: 5244 - R: 9815 G: 8383 B: 6559 C: 25313  
left Color Temp: 4369 K - Lux: 7323 - R: 10446 G: 10575 B: 8165 C: 29442  
left Color Temp: 4790 K - Lux: 9255 - R: 11302 G: 12865 B: 10085 C: 34861  
left Color Temp: 2972 K - Lux: 2637 - R: 9017 G: 5315 B: 3858 C: 17793  

TCS34725 connected to GPIO25 SDA and GPIO13 SCL gave

Code: Select all

No left TCS34725 found ... check your connections
Found right sensor
right Color Temp: 3840 K - Lux: 426 - R: 795 G: 721 B: 620 C: 1526  
right Color Temp: 3836 K - Lux: 432 - R: 803 G: 729 B: 625 C: 1545  
right Color Temp: 3833 K - Lux: 429 - R: 801 G: 726 B: 623 C: 1539  
right Color Temp: 3838 K - Lux: 428 - R: 798 G: 724 B: 622 C: 1531  
right Color Temp: 3845 K - Lux: 426 - R: 795 G: 722 B: 621 C: 1526  
right Color Temp: 3840 K - Lux: 426 - R: 796 G: 722 B: 621 C: 1527  
right Color Temp: 7523 K - Lux: 8046 - R: 5180 G: 10030 B: 8338 C: 24398  
right Color Temp: 6638 K - Lux: 11877 - R: 8103 G: 14367 B: 11160 C: 34891  
right Color Temp: 6964 K - Lux: 18521 - R: 12171 G: 22494 B: 17804 C: 54352  
right Color Temp: 6337 K - Lux: 14565 - R: 11338 G: 18386 B: 14719 C: 45763  
right Color Temp: 5725 K - Lux: 12307 - R: 10771 G: 15695 B: 12253 C: 39822  
right Color Temp: 5324 K - Lux: 10189 - R: 9795 G: 13160 B: 10113 C: 33899  
right Color Temp: 5376 K - Lux: 10697 - R: 10389 G: 13954 B: 10868 C: 36143  
right Color Temp: 5096 K - Lux: 14725 - R: 14843 G: 19077 B: 14436 C: 49198  
right Color Temp: 4199 K - Lux: 8809 - R: 11393 G: 11819 B: 8398 C: 31603  
right Color Temp: 5237 K - Lux: 12093 - R: 11913 G: 15690 B: 12028 C: 40372  
right Color Temp: 5160 K - Lux: 11412 - R: 11795 G: 15068 B: 11669 C: 39250  
right Color Temp: 5160 K - Lux: 11412 - R: 11795 G: 15068 B: 11669 C: 39250  
right Color Temp: 4935 K - Lux: 11054 - R: 12811 G: 15166 B: 11919 C: 40665  
right Color Temp: 4708 K - Lux: 10145 - R: 12826 G: 14245 B: 11168 C: 38672  
right Color Temp: 4361 K - Lux: 9094 - R: 13136 G: 13214 B: 10243 C: 36838  
right Color Temp: 5027 K - Lux: 11236 - R: 13247 G: 15707 B: 12644 C: 42348  
right Color Temp: 5121 K - Lux: 11741 - R: 13403 G: 16281 B: 13123 C: 43616  
right Color Temp: 5131 K - Lux: 10357 - R: 11655 G: 14265 B: 11442 C: 37878  

did not attach pullups - there appear to be pullups on the TCS34725 PCB
what else do you have attached to the ESP32? could be having power supply problems