TWI Scanner no device was found

RE: TWI Scanner no device was found

Baha Louati — Fri, 26 Feb 2021 11:26:42 GMT

I figured out how to make the TWI Scanner example detects my Sensor, I sent an I2C " ADC read" Command to the sensor address before the scanning starts ( the sensor was MS5803 ) and now its detectable . Good luck for others out there.

RE: TWI Scanner no device was found

Baha Louati — Wed, 24 Feb 2021 07:04:32 GMT

That's Completely understandable!

I have 3 sensors ( connected via Qwiic). I checked and all 3 of my sensors are detectable in the Arduino code, yet in Segger embedded studio only two of them were detected. it seems arduino code is doing something Segger isn't? I have to check!

Thanks so much for your reply, Your fast response is really valuable. Hoping you have a wonderful day Steven!

RE: TWI Scanner no device was found

StevenW807 — Tue, 23 Feb 2021 22:16:02 GMT

Also, try the Arduino demo code (easier to use than nRF5) to test the hardware. Arduino community has so many libraries & demo codes, all free to use, very handy. Then, Learn Arduino code (C++), translate the code to Nordic code (C).

If you have an oscilloscope and logic analyzer, measure the I2C signals (SDA and SCL). Find out the signal information (e.g. address is correct? ACK exists? sending command is correct? )

RE: TWI Scanner no device was found

StevenW807 — Tue, 23 Feb 2021 22:10:16 GMT

Sorry, Baha.

Since it's the company product, I cannot share the code. My suggestion is to read the datasheet + check the hardware connection.

Hints

1. Some sensors need to wait for a few us or ms after sending the command. e.g. delay 27 us after sending command

2. Also, some sensors need to be initialized at the beginning.

3. You may ask your supplier for software / debugging issue.

4. Use the print function (e.g. NRF_LOG_INFO() ) to debug, see where the error is.

RE: TWI Scanner no device was found

Baha Louati — Tue, 23 Feb 2021 16:38:55 GMT

Could you please Share the code? I am having the same problem.

RE: TWI Scanner no device was found

StevenW807 — Mon, 22 Feb 2021 04:07:07 GMT

Problem Solved!

The code doesn't work due to the slave device and time delay issue. The sensor I'm using requires:

1) reset-->send continuous mode command-->read data (I didn't add reset command before)

2) meanwhile, for each read/write command, we must add a time delay (e.g. 5 ms) after the command

Thanks to everyone who helped me before! Cheers

RE: TWI Scanner no device was found

Charlie — Fri, 05 Feb 2021 11:56:08 GMT

Hi Steven,

I have some suggestions that may helpful for your debugging:

1. Did you check with Arduino again to make sure the device is still alive?

2. Can you try with the original twi_scanner example?

3. Do you have a logic analyzer to see what happens on the TWI bus? Please double check the wires' connectability.

Best regards,

Charlie

RE: TWI Scanner no device was found

StevenW807 — Fri, 05 Feb 2021 03:35:39 GMT

Note: my sensor returns 9 bytes of data (2 bytes of pressure, 1 byte of Check, 2 bytes of temperature, 1 byte of Check, 2 bytes of scaling factor, 1 byte of Check)