I2C device gets detected with Adafruit Bootloader but fails with Nordic SDK

[shockline]

I am trying to make PN7150 work with nRF52840 using TWI Communication.

Problem :
PN7150 gets detected with I2C scanner example when using Adafruit Bootloader and programmed using Arduino IDE.
But when I am using TWI Scanner example in Nordic SDK15. The address is not detected.

Background :
When TWI scanner example failed to detect address of PN7150 but worked with other devices. I thought maybe PN7150 is not getting enough voltage. I tried several ways. Used nRF52840 in high voltage mode. Used a level shifter. It all failed to detect the address.

I then tried I2C scanner example for Arduino using Adafruit's Bootloader and surprisingly it detected the correct address.

Maybe this problem is due to different implementation of I2C protocol in Arduino and Nordic SDK.

[Turbo J]

That is the point I'd take out the DSO (digital storage oscilloscope) and measure the actual I²C bus lines.

Note that I²C are 7-bit and used in either shifted form.
This could bite you here: NRF uses the right shifted addresses in the hardware (address in bits 6..0 without the R/W bit).

[Jørgen Holmefjord]

Hi,

• Which board are you running this on? An nRF52840-DK, an Adafruit board, or a custom board?
• Which voltage level do you supply the chip with? Have you measured the voltage on the GPIOs?
• Which GPIOs do you use to connect the I2C device? Are you using the same pins in both examples?

Best regards,
Jørgen

[shockline]

• I am running it on nrf52840-DK.
• Yes, I measured the GPIO voltage and it was 2.96V.
• For I2C communication I use P0.27 and P0.26. I use the same pins in both the examples.

[Jørgen Holmefjord]

Which SDK version are you testing with?

Did you check the GPIO voltage on both firmwares?

The PN7150 that you connect to, is this some kind of development kit/breakout board? In that case, can you provide a link?

Is the device designed for running at 3 V, without any level converters, etc?

[Mojo]

Try this driver.  It works much better.  We used it in all our projects.

https://github.com/IOsonata/IOsonata/blob/master/ARM/Nordic/src/i2c_nrf5x.cpp