Connection of a DS18B20 on a Arduino pro mini

Question

I'm actually trying to connect a DS18B20 sensor to a homemade board build with a ATmega328P processor running with a power of 3.3V and at 8 Mhz.

In order to get the address I wired the board as the following schematic on the pin 5 of my board. wire diagram (edited)

To power the sensor and the pull up resistor I use the VDD output of my board which provides 3.3V.

For the code part I uploaded this:

// This sketch looks for 1-wire devices and
// prints their addresses (serial number) to
// the UART, in a format that is useful in Arduino sketches
// Tutorial: 
// http://www.hacktronics.com/Tutorials/arduino-1-wire-address-finder.html
#include <OneWire.h>
OneWire ds(5); // Connect your 1-wire device to pin 5
void setup(void) {
 Serial.begin(9600);
 discoverOneWireDevices();
}
void discoverOneWireDevices(void) {
 byte i;
 byte present = 0;
 byte data[12];
 byte addr[8];
 Serial.print("Looking for 1-Wire devices...\n\r");
 while(ds.search(addr)) {
 Serial.print("\n\rFound \'1-Wire\' device with address:\n\r");
 for( i = 0; i < 8; i++) {
 Serial.print("0x");
 if (addr[i] < 16) {
 Serial.print('0');
 }
 Serial.print(addr[i], HEX);
 if (i < 7) {
 Serial.print(", ");
 }
 }
 if ( OneWire::crc8( addr, 7) != addr[7]) {
 Serial.print("CRC is not valid!\n");
 return;
 }
 }
 Serial.print("\n\r\n\rThat's it.\r\n");
 ds.reset_search();
 return;
}
void loop(void) {
 // nothing to see here
}

When I make it run on an Arduino Uno card I can get the address of the sensor but when I make it run on my card I only obtain this:

Looking for 1-Wire devices...

That's it.

Anyone got a idea why it's working on an Arduino Uno but not on my card?

hardware schematic

• domen: On schematic two pins are connected, in question description and code, there's only one pin.
• Jot: Is that a mosfet? Is it used to shortcut the data to 3.3v? why?
• Maxence Ginet: Sorry @domen i had put the wrong diagram in my post, i edited my post
• domen: You're saying it's same chip (and similar surrounding hardware) and same software? Is there a schematic for your own hardware, because you've probably made some mistake there. Include the details of all differences to working setup.
• Maxence Ginet: @domen i added in the post a hardware shematic around the chip , we use the PD5 (D5 )

Answer 1

I finally made it work, thx @domen.

I looked at the other part of the schematic and found I was using the wrong pin - I have two LDO and the one I was using was deactivated for sensor.

Thanks all for your help.