ESP32 Forum

Hi all,
We’re working on a custom PCB under our startup “Slogfy” where we’ve integrated the CY8C20110-SX2I capacitive touch IC with an ESP32 microcontroller. However, we’re not able to receive any data or touch status over I2C.
IC: CY8C20110-SX2I
Microcontroller: ESP32 (using Arduino IDE)
I2C Pins: SDA = GPIO21, SCL = GPIO22
Pull-ups: 4.7kΩ on SDA and SCL
I2C Address: 0x00 (or configured value)
Status: ESP32 detects device on I2C bus with scanner, but data read always returns 0 or fails.
We’ve attached:
Our Schematic (PDF/image)
PCB layout (image)
Screenshot of serial output and code snippet

Things we've tried:
Confirmed 3.3V and GND supply is OK


Confirmed I2C lines with logic analyzer (optional)


Tried different delays and requestFrom() patterns


Used both Wire.h and other I2C libraries



Please help us identify what might be wrong—whether in hardware, address configuration, reset handling, or timing.
Thanks in advance
– Team Slogfy

[img][/img]

How did you 'confirm' the I2C lines with a logic analyzer? Can you post the traces here?

#include <Wire.h>

#define SDA_PIN 21 // Use GPIO21 for SDA
#define SCL_PIN 22 // Use GPIO22 for SCL

void setup() {
// Initialize serial communication
Serial.begin(115200);
delay(1000); // Give time for serial monitor to connect

// Initialize I2C with specified SDA and SCL pins
Wire.begin(SDA_PIN, SCL_PIN);

Serial.println(" I2C Scanner Starting...");
Serial.print("Using SDA: GPIO");
Serial.print(SDA_PIN);
Serial.print(" | SCL: GPIO");
Serial.println(SCL_PIN);
}

void loop() {
byte error, address;
int count = 0;

Serial.println("Scanning for I2C devices...");

for (address = 1; address < 127; address++) {
Wire.beginTransmission(address);
error = Wire.endTransmission();

if (error == 0) {
Serial.print("I2C device found at address 0x");
if (address < 16)
Serial.print("0");
Serial.println(address, HEX);
count++;
}
}

if (count == 0)
Serial.println("No I2C devices found.");
else
Serial.println("I2C Scan Complete.\n");

delay(3000); // Scan every 3 seconds
}



"serial print is-No I2C devices found."