TWI scanner with two nrf52840 boards

Question

Hello, 
 I am using two nrf52840 DK boards, I tried to run TWI scanner example on one of the boards of SDK 15.0 example. I'm not getting the other device address it is giving message as "no device detected". I have connected the SCL and SDA pins respectively and given the power supply from the board in which twi scanner example is running to other board with external supply pins(Even if I have connected with two cables for supply independently not getting the address). 
 
 Kindly, suggest the possible method to find the address of the nrf52840 board .

awneil · Accepted Answer

Shashi said: when i have connected to another sdk(nrf52840) it is showing as "no device was found" 
 So, again, have you programmed an I2C slave into that other DK? 
 If you have both the MAX30100 and the 2nd DK connected, is the MAX30100 still detected? 
 Have you looked at the I2C lines with an oscilloscope or analyser to see what is happening? 
 Shashi said: How exactly can i get the address ? 
 Again, when you're making an I2C Slave on any microcontroller, then you assign its address in your code! 
 Note: 
 To take a screenshot on a Windows computer: 
 
 Use the ' PrintScreen ' (sometimes abbreviated; eg, 'PrtSc') button to capture the entire screen; 
 Use Alt+ PrintScreen to capture just the active window.

awneil · Answer

Shashi said: I have not programmed I2C slave in other DK 
 You need to! 
 Just like you have to write code to use the TWI peripheral code in Master mode! 
 Without code to control it, the TWI peripheral does nothing . 
 Shashi said: How do i assign I2C slave to any controller 
 That will depend on the particular microcontroller - it will be different in an nRF52 from an STM32. 
 You will have to study the documentation for the particular microcontroller to find out what is required. 
 Shashi said: can you give a code snippet ? 
 There are examples for Nordic chips in the Nordic SDK. 
 ST provide their own examples for their own chips.

TWI scanner with two nrf52840 boards

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