nRF Connect SDK Fundamentals Lesson 6 exercise 1: Error with i2c_write_read_dt

RE: nRF Connect SDK Fundamentals Lesson 6 exercise 1: Error with i2c_write_read_dt

Menon — Mon, 09 Feb 2026 14:38:43 GMT

Hello,

Great to hear that your issue has been resolved.

[quote user="LonnieB"]And this solved the problem. Kazi later wrote "That's the fix for now as there is bug in the "nordic,nrf-twi" driver in ncs v3.2.1." It would be great if you highlighted that for beginners like me taking the SDK Fundamentals course.[/quote]

I will discuss this with Kazi and update the exercise accordingly.

Kind Regards,

Abhijith

RE: nRF Connect SDK Fundamentals Lesson 6 exercise 1: Error with i2c_write_read_dt

LonnieB — Mon, 09 Feb 2026 13:31:36 GMT

Thanks for getting back to me. I searched DevZone several times and found a similar issue in the post "I2C write-restart-read issue on nRF Connect SDK v3.2.x". Kazi Afroza Sultana suggested the following addition in the device tree overlay:

&i2c1 {
status = "okay";
compatible = "nordic,nrf-twim"; <-- this line is added
i2cclock: i2cclock@68 {
compatible = "i2c-device";
label = "I2CCLOCK";
reg = <0x68>;
};
};

And this solved the problem. Kazi later wrote "That's the fix for now as there is bug in the "nordic,nrf-twi" driver in ncs v3.2.1." It would be great if you highlighted that for beginners like me taking the SDK Fundamentals course.

RE: nRF Connect SDK Fundamentals Lesson 6 exercise 1: Error with i2c_write_read_dt

Menon — Mon, 09 Feb 2026 10:18:03 GMT

Hello,

Sorry for the delay in getting back to you.I was sick and out of the office.

I see from your response that you were able to collect the logs from the device. From what I can tell, this might be a physical connection issue. Please make sure you are following the connection setup shown below for the nRF52840 DK.

Are you using the same setup? If possible, could you please share a picture of your physical connections?

Kind Regards,

Abhijith

RE: nRF Connect SDK Fundamentals Lesson 6 exercise 1: Error with i2c_write_read_dt

LonnieB — Fri, 06 Feb 2026 19:51:00 GMT

One addition. I deleted the build file for l6_e1_sol, and I added the parameters in the prj.conf file to provide the i2c_dump_messages. I rebuilt and have this output:

*** Booting nRF Connect SDK v3.2.1-d8887f6f32df ***
*** Using Zephyr OS v4.2.99-ec78104f1569 ***
[00:00:00.249,908] <dbg> i2c: i2c_dump_msgs_rw: I2C msg: i2c@40003000, addr=76
[00:00:00.249,938] <dbg> i2c: i2c_dump_msgs_rw: W len=01: d0
[00:00:00.249,969] <dbg> i2c: i2c_dump_msgs_rw: R Sr P len=01: 00
Failed to read register d0

However the logic analyzer still shows the same data as the first screenshot in my first message:

Start, write to 0x76, ACK-Slave, 0xd0, ACK-Master - and that is all, no Read, no restart, no data, and no Stop - even though these are indicated in the i2c_dump_messages data above

RE: nRF Connect SDK Fundamentals Lesson 6 exercise 1: Error with i2c_write_read_dt

LonnieB — Tue, 03 Feb 2026 19:10:50 GMT

Hi,

Thank you so much for your help. I'm new to nRF connect and Nordic - so bear with me. I don't know where to find the device logs you are looking for -and google wasn't much help. Also, I think I may have pasted the wrong device overlay file (the one I pasted was from a DevZone ticket I was looking at.. sorry. Finally, I am using the exact files for Lesson 6 Exercise 1 - except that I changed the overlay to account for the I2C device address of 00x76 instead of 0x77. When I build and flash the solution, I get the same errors. Additionally, I noticed errors in the Problems tab if I have the Device Overlay file open - like I saw with the prj.conf file. I am attaching the list of errors from the Problems Tab. And just to be clear, the device overlay is pasted here:

// To get started, press Ctrl+Space to bring up the completion menu and view the available nodes.

// For more help, browse the DeviceTree documentation at https://docs.zephyrproject.org/latest/guides/dts/index.html

&i2c0 {

status = "okay";

pinctrl-0 = <&i2c0_default>;

pinctrl-1 = <&i2c0_sleep>;

pinctrl-names = "default", "sleep";

mysensor: mysensor@76{

compatible = "i2c-device";

status = "okay";

reg = < 0x76 >;

};

&pinctrl {

/omit-if-no-ref/ i2c0_default: i2c0_default {

group1 {

psels = <NRF_PSEL(TWIM_SCL, 1, 14)>,

<NRF_PSEL(TWIM_SDA, 1, 15)>;

};

/omit-if-no-ref/ i2c0_sleep: i2c0_sleep {

group1 {

psels = <NRF_PSEL(TWIM_SCL, 1, 14)>,

<NRF_PSEL(TWIM_SDA, 1, 15)>;

low-power-enable;

};

Thanks again, Lonnie

[{
"resource": "/C:/ncs/v3.2.1/zephyr/dts/vendor/nordic/nrf52840_partition.dtsi",
"owner": "DeviceTree",
"severity": 4,
"message": "You are using Partition Manager to define the partitions. Devicetree definitions are ignored for this build.",
"startLineNumber": 16,
"startColumn": 2,
"endLineNumber": 16,
"endColumn": 12,
"modelVersionId": 1,
"origin": "extHost1"
}]

[{
"resource": "/C:/myfw/ncs-fund/ncs-fund/l6/l6_e1_sol/boards/nrf52840dk_nrf52840.overlay",
"owner": "DeviceTree",
"severity": 2,
"message": "Pin 14 of &gpio1 already assigned to &spi3 • MISO",
"startLineNumber": 6,
"startColumn": 17,
"endLineNumber": 6,
"endColumn": 32,
"relatedInformation": [
{
"startLineNumber": 281,
"startColumn": 14,
"endLineNumber": 281,
"endColumn": 29,
"message": "Overlapping assignment",
"resource": "/c:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts"
},
{
"startLineNumber": 282,
"startColumn": 14,
"endLineNumber": 282,
"endColumn": 27,
"message": "Overlapping assignment",
"resource": "/c:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts"
}
],
"modelVersionId": 7,
"origin": "extHost1"
},{
"resource": "/C:/myfw/ncs-fund/ncs-fund/l6/l6_e1_sol/boards/nrf52840dk_nrf52840.overlay",
"owner": "DeviceTree",
"severity": 2,
"message": "Pin 15 of &gpio1 already assigned to &spi3 • SCK",
"startLineNumber": 6,
"startColumn": 17,
"endLineNumber": 6,
"endColumn": 32,
"relatedInformation": [
{
"startLineNumber": 281,
"startColumn": 14,
"endLineNumber": 281,
"endColumn": 29,
"message": "Overlapping assignment",
"resource": "/c:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts"
},
{
"startLineNumber": 282,
"startColumn": 14,
"endLineNumber": 282,
"endColumn": 27,
"message": "Overlapping assignment",
"resource": "/c:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts"
}
],
"modelVersionId": 7,
"origin": "extHost1"
},{
"resource": "/C:/myfw/ncs-fund/ncs-fund/l6/l6_e1_sol/boards/nrf52840dk_nrf52840.overlay",
"owner": "DeviceTree",
"severity": 2,
"message": "Pin 14 of &gpio1 already assigned to &spi3 • MISO",
"startLineNumber": 7,
"startColumn": 14,
"endLineNumber": 7,
"endColumn": 27,
"relatedInformation": [
{
"startLineNumber": 281,
"startColumn": 14,
"endLineNumber": 281,
"endColumn": 29,
"message": "Overlapping assignment",
"resource": "/c:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts"
},
{
"startLineNumber": 282,
"startColumn": 14,
"endLineNumber": 282,
"endColumn": 27,
"message": "Overlapping assignment",
"resource": "/c:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts"
}
],
"modelVersionId": 7,
"origin": "extHost1"
},{
"resource": "/C:/myfw/ncs-fund/ncs-fund/l6/l6_e1_sol/boards/nrf52840dk_nrf52840.overlay",
"owner": "DeviceTree",
"severity": 2,
"message": "Pin 15 of &gpio1 already assigned to &spi3 • SCK",
"startLineNumber": 7,
"startColumn": 14,
"endLineNumber": 7,
"endColumn": 27,
"relatedInformation": [
{
"startLineNumber": 281,
"startColumn": 14,
"endLineNumber": 281,
"endColumn": 29,
"message": "Overlapping assignment",
"resource": "/c:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts"
},
{
"startLineNumber": 282,
"startColumn": 14,
"endLineNumber": 282,
"endColumn": 27,
"message": "Overlapping assignment",
"resource": "/c:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts"
}
],
"modelVersionId": 7,
"origin": "extHost1"
}]

[{
"resource": "/C:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts",
"owner": "DeviceTree",
"severity": 2,
"message": "Pin 13 of &gpio0 already assigned to &pwm0 • OUT0",
"startLineNumber": 32,
"startColumn": 20,
"endLineNumber": 32,
"endColumn": 22,
"relatedInformation": [
{
"startLineNumber": 220,
"startColumn": 14,
"endLineNumber": 220,
"endColumn": 29,
"message": "Overlapping assignment",
"resource": "/c:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts"
},
{
"startLineNumber": 221,
"startColumn": 14,
"endLineNumber": 221,
"endColumn": 27,
"message": "Overlapping assignment",
"resource": "/c:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts"
}
],
"modelVersionId": 1,
"origin": "extHost1"
},{
"resource": "/C:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts",
"owner": "DeviceTree",
"severity": 2,
"message": "Pin 13 of &gpio0 already assigned to &led0",
"startLineNumber": 220,
"startColumn": 14,
"endLineNumber": 220,
"endColumn": 29,
"relatedInformation": [
{
"startLineNumber": 32,
"startColumn": 20,
"endLineNumber": 32,
"endColumn": 22,
"message": "Overlapping assignment",
"resource": "/c:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts"
}
],
"modelVersionId": 1,
"origin": "extHost1"
},{
"resource": "/C:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts",
"owner": "DeviceTree",
"severity": 2,
"message": "Pin 13 of &gpio0 already assigned to &led0",
"startLineNumber": 221,
"startColumn": 14,
"endLineNumber": 221,
"endColumn": 27,
"relatedInformation": [
{
"startLineNumber": 32,
"startColumn": 20,
"endLineNumber": 32,
"endColumn": 22,
"message": "Overlapping assignment",
"resource": "/c:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts"
}
],
"modelVersionId": 1,
"origin": "extHost1"
},{
"resource": "/C:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts",
"owner": "DeviceTree",
"severity": 2,
"message": "Pin 14 of &gpio1 already assigned to &i2c0 • SCL",
"startLineNumber": 281,
"startColumn": 14,
"endLineNumber": 281,
"endColumn": 29,
"relatedInformation": [
{
"startLineNumber": 6,
"startColumn": 17,
"endLineNumber": 6,
"endColumn": 32,
"message": "Overlapping assignment",
"resource": "/c:/myfw/ncs-fund/ncs-fund/l6/l6_e1_sol/boards/nrf52840dk_nrf52840.overlay"
},
{
"startLineNumber": 7,
"startColumn": 14,
"endLineNumber": 7,
"endColumn": 27,
"message": "Overlapping assignment",
"resource": "/c:/myfw/ncs-fund/ncs-fund/l6/l6_e1_sol/boards/nrf52840dk_nrf52840.overlay"
}
],
"modelVersionId": 1,
"origin": "extHost1"
},{
"resource": "/C:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts",
"owner": "DeviceTree",
"severity": 2,
"message": "Pin 15 of &gpio1 already assigned to &i2c0 • SDA",
"startLineNumber": 281,
"startColumn": 14,
"endLineNumber": 281,
"endColumn": 29,
"relatedInformation": [
{
"startLineNumber": 6,
"startColumn": 17,
"endLineNumber": 6,
"endColumn": 32,
"message": "Overlapping assignment",
"resource": "/c:/myfw/ncs-fund/ncs-fund/l6/l6_e1_sol/boards/nrf52840dk_nrf52840.overlay"
},
{
"startLineNumber": 7,
"startColumn": 14,
"endLineNumber": 7,
"endColumn": 27,
"message": "Overlapping assignment",
"resource": "/c:/myfw/ncs-fund/ncs-fund/l6/l6_e1_sol/boards/nrf52840dk_nrf52840.overlay"
}
],
"modelVersionId": 1,
"origin": "extHost1"
},{
"resource": "/C:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts",
"owner": "DeviceTree",
"severity": 2,
"message": "Pin 14 of &gpio1 already assigned to &i2c0 • SCL",
"startLineNumber": 282,
"startColumn": 14,
"endLineNumber": 282,
"endColumn": 27,
"relatedInformation": [
{
"startLineNumber": 6,
"startColumn": 17,
"endLineNumber": 6,
"endColumn": 32,
"message": "Overlapping assignment",
"resource": "/c:/myfw/ncs-fund/ncs-fund/l6/l6_e1_sol/boards/nrf52840dk_nrf52840.overlay"
},
{
"startLineNumber": 7,
"startColumn": 14,
"endLineNumber": 7,
"endColumn": 27,
"message": "Overlapping assignment",
"resource": "/c:/myfw/ncs-fund/ncs-fund/l6/l6_e1_sol/boards/nrf52840dk_nrf52840.overlay"
}
],
"modelVersionId": 1,
"origin": "extHost1"
},{
"resource": "/C:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts",
"owner": "DeviceTree",
"severity": 2,
"message": "Pin 15 of &gpio1 already assigned to &i2c0 • SDA",
"startLineNumber": 282,
"startColumn": 14,
"endLineNumber": 282,
"endColumn": 27,
"relatedInformation": [
{
"startLineNumber": 6,
"startColumn": 17,
"endLineNumber": 6,
"endColumn": 32,
"message": "Overlapping assignment",
"resource": "/c:/myfw/ncs-fund/ncs-fund/l6/l6_e1_sol/boards/nrf52840dk_nrf52840.overlay"
},
{
"startLineNumber": 7,
"startColumn": 14,
"endLineNumber": 7,
"endColumn": 27,
"message": "Overlapping assignment",
"resource": "/c:/myfw/ncs-fund/ncs-fund/l6/l6_e1_sol/boards/nrf52840dk_nrf52840.overlay"
}
],
"modelVersionId": 1,
"origin": "extHost1"
}]

[{
"resource": "/C:/ncs/v3.2.1/zephyr/dts/arm/nordic/nrf52840.dtsi",
"owner": "DeviceTree",
"severity": 2,
"message": "Address range collides with power@40000000 (both start at 0x40000000)",
"startLineNumber": 67,
"startColumn": 10,
"endLineNumber": 67,
"endColumn": 29,
"relatedInformation": [
{
"startLineNumber": 72,
"startColumn": 10,
"endLineNumber": 72,
"endColumn": 24,
"message": "power@40000000 declared here",
"resource": "/c:/ncs/v3.2.1/zephyr/dts/arm/nordic/nrf52840.dtsi"
}
],
"modelVersionId": 1,
"origin": "extHost1"
},{
"resource": "/C:/ncs/v3.2.1/zephyr/dts/arm/nordic/nrf52840.dtsi",
"owner": "DeviceTree",
"severity": 2,
"message": "Address range collides with clock@40000000 (both start at 0x40000000)",
"startLineNumber": 74,
"startColumn": 10,
"endLineNumber": 74,
"endColumn": 29,
"relatedInformation": [
{
"startLineNumber": 65,
"startColumn": 10,
"endLineNumber": 65,
"endColumn": 24,
"message": "clock@40000000 declared here",
"resource": "/c:/ncs/v3.2.1/zephyr/dts/arm/nordic/nrf52840.dtsi"
}
],
"modelVersionId": 1,
"origin": "extHost1"
},{
"resource": "/C:/ncs/v3.2.1/zephyr/dts/arm/nordic/nrf52840.dtsi",
"owner": "DeviceTree",
"severity": 2,
"message": "Address range collides with flash-controller@4001e000 (both start at 0x4001e000)",
"startLineNumber": 417,
"startColumn": 10,
"endLineNumber": 417,
"endColumn": 29,
"relatedInformation": [
{
"startLineNumber": 421,
"startColumn": 21,
"endLineNumber": 421,
"endColumn": 46,
"message": "flash-controller@4001e000 declared here",
"resource": "/c:/ncs/v3.2.1/zephyr/dts/arm/nordic/nrf52840.dtsi"
}
],
"modelVersionId": 1,
"origin": "extHost1"
},{
"resource": "/C:/ncs/v3.2.1/zephyr/dts/arm/nordic/nrf52840.dtsi",
"owner": "DeviceTree",
"severity": 2,
"message": "Address range collides with acl@4001e000 (both start at 0x4001e000)",
"startLineNumber": 423,
"startColumn": 10,
"endLineNumber": 423,
"endColumn": 29,
"relatedInformation": [
{
"startLineNumber": 415,
"startColumn": 8,
"endLineNumber": 415,
"endColumn": 20,
"message": "acl@4001e000 declared here",
"resource": "/c:/ncs/v3.2.1/zephyr/dts/arm/nordic/nrf52840.dtsi"
}
],
"modelVersionId": 1,
"origin": "extHost1"
}]

RE: nRF Connect SDK Fundamentals Lesson 6 exercise 1: Error with i2c_write_read_dt

Menon — Tue, 03 Feb 2026 15:30:55 GMT

Hello,

Thanks for sharing the logs. However, these look like build logs, whereas I was hoping to see the device logs that show the I2C error. From what I can tell, the issue in this log doesn’t really look like an I2C problem.

I tried building the same sample on my side and couldn’t reproduce the issue. This looks more like a VS Code related issue, or at least not an I2C issue.

In your overlay, I see that i2c21 is being used, could you please double-check whether that might be the problem? I’d recommend trying the solution from the same exercise once and seeing if the issue still occurs.

Kind regards,
Abhijith

RE: nRF Connect SDK Fundamentals Lesson 6 exercise 1: Error with i2c_write_read_dt

LonnieB — Mon, 02 Feb 2026 18:19:48 GMT

I am having trouble attaching the log in the <code> section of insert - so the log is attached below. The "Problems" Tab is included at the end of the log file. I am using nRF Connect SDK 3.2.1.

The problem is only on the DK. The feather, which is programed from the Arduino IDE using Adafruit bluefruit and BME280 libraries, works fine.

* Executing task: nRF Connect: Build [pristine]: l6_e1/build

Building l6_e1
west build --build-dir c:/myfw/ncs-fund/ncs-fund/l6/l6_e1/build c:/myfw/ncs-fund/ncs-fund/l6/l6_e1 --pristine --board nrf52840dk/nrf52840 -- -DCONF_FILE="prj.conf" -DDTC_OVERLAY_FILE=boards/nrf52840dk_nrf52840.overlay -DDEBUG_THREAD_INFO=On -DCONFIG_DEBUG_THREAD_INFO=y -Dl6_e1_DEBUG_THREAD_INFO=On

-- west build: generating a build system
Loading Zephyr module(s) (Zephyr base): sysbuild_default
-- Found Python3: C:/ncs/toolchains/66cdf9b75e/opt/bin/python.exe (found suitable version "3.12.4", minimum required is "3.10") found components: Interpreter
-- Cache files will be written to: C:/ncs/v3.2.1/zephyr/.cache
-- Found west (found suitable version "1.4.0", minimum required is "0.14.0")
-- Board: nrf52840dk, qualifiers: nrf52840
Parsing C:/ncs/v3.2.1/zephyr/share/sysbuild/Kconfig
Loaded configuration 'C:/myfw/ncs-fund/ncs-fund/l6/l6_e1/build/_sysbuild/empty.conf'
Merged configuration 'C:/myfw/ncs-fund/ncs-fund/l6/l6_e1/build/_sysbuild/empty.conf'
Configuration saved to 'C:/myfw/ncs-fund/ncs-fund/l6/l6_e1/build/zephyr/.config'
Kconfig header saved to 'C:/myfw/ncs-fund/ncs-fund/l6/l6_e1/build/_sysbuild/autoconf.h'
--
***************************
* Running CMake for l6_e1 *
***************************

Loading Zephyr default modules (Zephyr base).
-- Application: C:/myfw/ncs-fund/ncs-fund/l6/l6_e1
-- CMake version: 3.21.0
-- Found Python3: C:/ncs/toolchains/66cdf9b75e/opt/bin/python.exe (found suitable version "3.12.4", minimum required is "3.10") found components: Interpreter
-- Cache files will be written to: C:/ncs/v3.2.1/zephyr/.cache
-- Zephyr version: 4.2.99 (C:/ncs/v3.2.1/zephyr)
-- Found west (found suitable version "1.4.0", minimum required is "0.14.0")
-- Board: nrf52840dk, qualifiers: nrf52840
-- Found host-tools: zephyr 0.17.0 (C:/ncs/toolchains/66cdf9b75e/opt/zephyr-sdk)
-- Found toolchain: zephyr 0.17.0 (C:/ncs/toolchains/66cdf9b75e/opt/zephyr-sdk)
-- Found Dtc: C:/ncs/toolchains/66cdf9b75e/opt/bin/dtc.exe (found suitable version "1.4.7", minimum required is "1.4.6")
-- Found BOARD.dts: C:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840.dts
-- Found devicetree overlay: boards/nrf52840dk_nrf52840.overlay
-- Generated zephyr.dts: C:/myfw/ncs-fund/ncs-fund/l6/l6_e1/build/l6_e1/zephyr/zephyr.dts
-- Generated pickled edt: C:/myfw/ncs-fund/ncs-fund/l6/l6_e1/build/l6_e1/zephyr/edt.pickle
-- Generated devicetree_generated.h: C:/myfw/ncs-fund/ncs-fund/l6/l6_e1/build/l6_e1/zephyr/include/generated/zephyr/devicetree_generated.h
Parsing C:/ncs/v3.2.1/zephyr/Kconfig
Loaded configuration 'C:/ncs/v3.2.1/zephyr/boards/nordic/nrf52840dk/nrf52840dk_nrf52840_defconfig'
Merged configuration 'C:/myfw/ncs-fund/ncs-fund/l6/l6_e1/prj.conf'
Merged configuration 'C:/myfw/ncs-fund/ncs-fund/l6/l6_e1/build/l6_e1/zephyr/misc/generated/extra_kconfig_options.conf'
Merged configuration 'C:/myfw/ncs-fund/ncs-fund/l6/l6_e1/build/l6_e1/zephyr/.config.sysbuild'
Configuration saved to 'C:/myfw/ncs-fund/ncs-fund/l6/l6_e1/build/l6_e1/zephyr/.config'
Kconfig header saved to 'C:/myfw/ncs-fund/ncs-fund/l6/l6_e1/build/l6_e1/zephyr/include/generated/zephyr/autoconf.h'
-- Found GnuLd: c:/ncs/toolchains/66cdf9b75e/opt/zephyr-sdk/arm-zephyr-eabi/arm-zephyr-eabi/bin/ld.bfd.exe (found version "2.38")
-- The C compiler identification is GNU 12.2.0
-- The CXX compiler identification is GNU 12.2.0
-- The ASM compiler identification is GNU
-- Found assembler: C:/ncs/toolchains/66cdf9b75e/opt/zephyr-sdk/arm-zephyr-eabi/bin/arm-zephyr-eabi-gcc.exe
-- Found gen_kobject_list: C:/ncs/v3.2.1/zephyr/scripts/build/gen_kobject_list.py
-- Configuring done
-- Generating done
-- Build files have been written to: C:/myfw/ncs-fund/ncs-fund/l6/l6_e1/build/l6_e1
-- Configuring done
-- Generating done
-- Build files have been written to: C:/myfw/ncs-fund/ncs-fund/l6/l6_e1/build
←[92m-- west build: building application
[5/10] Performing build step for 'l6_e1'
[4/168] Generating include/generated/zephyr/version.h
-- Zephyr version: 4.2.99 (C:/ncs/v3.2.1/zephyr), build: ncs-v3.2.1
[5/168] Generating include/generated/zephyr/syscall_dispatch.c, include/generated/zephyr/s[6/168] Generating include/generated/device-api-sections.ld, include/generated/device-api-[7/168] Generating include/generated/zephyr/syscall_dispatch.c, include/generated/zephyr/s[9/168] Building C object zephyr/CMakeFiles/offsets.dir/arch/arm/core/offsets/offsets.c.ob[10/168] Building C object zephyr/CMakeFiles/offsets.dir/arch/arm/core/offsets/offsets.c.o[11/168] Building C object zephyr/CMakeFiles/zephyr.dir/C_/ncs/v3.2.1/nrf/lib/boot_banner/[11/168] Building C object zephyr/CMakeFiles/zephyr.dir/C_/ncs/v3.2.1/nrf/subsys/partition[13/168] Building C object zephyr/CMakeFiles/zephyr.dir/C_/ncs/v3.2.1/nrfxlib/crypto/nrf_c[15/168] Building C object zephyr/soc/soc/nrf52840/CMakeFiles/soc__nordic.dir/validate_bin[18/168] Building C object zephyr/arch/arch/arm/core/cortex_m/CMakeFiles/arch__arm__core__[19/168] Building C object zephyr/arch/arch/arm/core/cortex_m/CMakeFiles/arch__arm__core__[20/168] Building ASM object zephyr/arch/arch/arm/core/cortex_m/CMakeFiles/arch__arm__core[21/168] Building C object zephyr/arch/arch/arm/core/cortex_m/CMakeFiles/arch__arm__core__[22/168] Building C object zephyr/arch/common/CMakeFiles/arch__common.dir/sw_isr_common.c.[26/168] Building C object zephyr/arch/arch/arm/core/CMakeFiles/arch__arm__core.dir/fatal.[27/168] Building C object zephyr/arch/arch/arm/core/CMakeFiles/arch__arm__core.dir/tls.c.[29/168] Building ASM object zephyr/arch/arch/arm/core/CMakeFiles/arch__arm__core.dir/nmi_[30/168] Building C object zephyr/arch/arch/arm/core/cortex_m/CMakeFiles/arch__arm__core__[31/168] Building C object zephyr/arch/arch/arm/core/cortex_m/CMakeFiles/arch__arm__core__[32/168] Building C object zephyr/arch/arch/arm/core/cortex_m/CMakeFiles/arch__arm__core__[34/168] Building ASM object zephyr/arch/arch/arm/core/cortex_m/CMakeFiles/arch__arm__core[36/168] Building ASM object zephyr/arch/arch/arm/core/cortex_m/CMakeFiles/arch__arm__core[37/168] Building ASM object zephyr/arch/arch/arm/core/cortex_m/CMakeFiles/arch__arm__core[38/168] Building C object zephyr/soc/soc/nrf52840/CMakeFiles/soc__nordic.dir/validate_bas[41/168] Building C object zephyr/arch/arch/arm/core/cortex_m/CMakeFiles/arch__arm__core__[43/168] Building ASM object zephyr/arch/arch/arm/core/cortex_m/CMakeFiles/arch__arm__core[44/168] Building C object zephyr/arch/arch/arm/core/mpu/CMakeFiles/arch__arm__core__mpu.d[46/168] Building C object zephyr/arch/arch/arm/core/mpu/CMakeFiles/arch__arm__core__mpu.d[47/168] Building C object zephyr/lib/libc/picolibc/CMakeFiles/lib__libc__picolibc.dir/ass[48/168] Building C object zephyr/lib/libc/picolibc/CMakeFiles/lib__libc__picolibc.dir/cbp[49/168] Building C object zephyr/lib/libc/picolibc/CMakeFiles/lib__libc__picolibc.dir/err[52/168] Building C object zephyr/lib/libc/picolibc/CMakeFiles/lib__libc__picolibc.dir/loc[53/168] Building C object zephyr/lib/libc/picolibc/CMakeFiles/lib__libc__picolibc.dir/std[56/168] Building C object zephyr/lib/libc/common/CMakeFiles/lib__libc__common.dir/source/[57/168] Building C object zephyr/lib/libc/common/CMakeFiles/lib__libc__common.dir/source/[59/168] Building C object zephyr/soc/soc/nrf52840/CMakeFiles/soc__nordic.dir/validate_ena[60/168] Building C object zephyr/soc/soc/nrf52840/CMakeFiles/soc__nordic.dir/common/reboo[61/168] Building C object zephyr/soc/soc/nrf52840/CMakeFiles/soc__nordic.dir/common/gpiot[62/168] Building C object zephyr/soc/soc/nrf52840/CMakeFiles/soc__nordic.dir/nrf52/soc.c.[63/168] Building C object zephyr/soc/soc/nrf52840/CMakeFiles/soc__nordic.dir/common/gppi_[65/168] Building C object zephyr/drivers/serial/CMakeFiles/drivers__serial.dir/uart_nrfx_[67/168] Building C object zephyr/drivers/console/CMakeFiles/drivers__console.dir/uart_con[69/168] Linking C static library zephyr\arch\arch\arm\core\cortex_m\libarch__arm__core__c[71/168] Building C object zephyr/drivers/i2c/CMakeFiles/drivers__i2c.dir/i2c_nrfx_twi_com[73/168] Building C object zephyr/drivers/i2c/CMakeFiles/drivers__i2c.dir/i2c_nrfx_twi.c.o[74/168] Building C object zephyr/drivers/pinctrl/CMakeFiles/drivers__pinctrl.dir/common.c[76/168] Building C object zephyr/drivers/timer/CMakeFiles/drivers__timer.dir/nrf_rtc_time[78/168] Building C object modules/nrf/drivers/hw_cc3xx/CMakeFiles/..__nrf__drivers__hw_cc[79/168] Building C object modules/hal_nordic/modules/hal_nordic/nrfx/CMakeFiles/modules__[81/168] Building C object modules/hal_nordic/modules/hal_nordic/nrfx/CMakeFiles/modules__hal_nordic__nrfx.dir/C_/ncs/v3.2.1/modules/hal/nordic/nrfx/bsp/stable/mdk/system_nrf52840.[82/168] Building C object modules/hal_nordic/modules/hal_nordic/nrfx/CMakeFiles/modules__[85/168] Building C object modules/hal_nordic/modules/hal_nordic/nrfx/CMakeFiles/modules__[87/168] Building C object modules/hal_nordic/modules/hal_nordic/nrfx/CMakeFiles/modules__hal_nordic__nrfx.dir/C_/ncs/v3.2.1/modules/hal/nordic/nrfx/helpers/nrfx_flag32_allocator.c[88/168] Building C object modules/hal_nordic/modules/hal_nordic/nrfx/CMakeFiles/modules__hal_nordic__nrfx.dir/C_/ncs/v3.2.1/modules/hal/nordic/nrfx/drivers/src/nrfx_clock_hfclk192[91/168] Building C object modules/hal_nordic/modules/hal_nordic/nrfx/CMakeFiles/modules__hal_nordic__nrfx.dir/C_/ncs/v3.2.1/modules/hal/nordic/nrfx/drivers/src/nrfx_clock_hfclkaud[92/168] Building C object modules/hal_nordic/modules/hal_nordic/nrfx/CMakeFiles/modules__[93/168] Building C object modules/hal_nordic/modules/hal_nordic/nrfx/CMakeFiles/modules__hal_nordic__nrfx.dir/C_/ncs/v3.2.1/modules/hal/nordic/nrfx/drivers/src/nrfx_clock_xo24m.c.[94/168] Building C object modules/hal_nordic/modules/hal_nordic/nrfx/CMakeFiles/modules__hal_nordic__nrfx.dir/C_/ncs/v3.2.1/modules/hal/nordic/nrfx/drivers/src/nrfx_clock_lfclk.c.[96/168] Building C object modules/hal_nordic/modules/hal_nordic/nrfx/CMakeFiles/modules__[97/168] Building C object modules/hal_nordic/modules/hal_nordic/nrfx/CMakeFiles/modules__[99/168] Building C object modules/hal_nordic/modules/hal_nordic/nrfx/CMakeFiles/modules__[100/168] Linking C static library modules\nrf\drivers\hw_cc3xx\lib..__nrf__drivers__hw_cc[136/168] Building C object modules/hal_nordic/modules/hal_nordic/nrfx/CMakeFiles/modules__hal_nordic__nrfx.dir/C_/ncs/v3.2.1/modules/hal/nordic/nrfx/drivers/src/nrfx_twi_twim.c.ob[139/168] Building C object modules/hal_nordic/modules/hal_nordic/nrfx/CMakeFiles/modules_[157/168] Linking C static library modules\hal_nordic\modules\hal_nordic\nrfx\libmodules__[159/168] Linking C static library modules\hal_nordic\modules\hal_nordic\nrfx\libmodules__[168/168] Linking C executable zephyr\zephyr.elf
Memory region Used Size Region Size %age Used
FLASH: 36188 B 1 MB 3.45%
RAM: 6784 B 256 KB 2.59%
IDT_LIST: 0 GB 32 KB 0.00%
Generating files from C:/myfw/ncs-fund/ncs-fund/l6/l6_e1/build/l6_e1/zephyr/zephyr.elf for board: nrf52840dk
[8/10] cmd.exe /C "cd /D C:\myfw\ncs-fund\ncs-fund\l6\l6_e1\build\_sysbuild && C:\ncs\tool[10/10] Generating ../merged.hex
* Terminal will be reused by tasks, press any key to close it.

Here is the Problems Tab:
The I2C drivers must be enabled by CONFIG_I2C to be included in the build

[{
"resource": "/c:/myfw/ncs-fund/ncs-fund/l6/l6_e1/prj.conf",
"owner": "Kconfig no context",
"severity": 2,
"message": "The active build context 'build' does not use this file.",
"startLineNumber": 1,
"startColumn": 1,
"endLineNumber": 1,
"endColumn": 1,
"modelVersionId": 1,
"origin": "extHost1"
}]

RE: nRF Connect SDK Fundamentals Lesson 6 exercise 1: Error with i2c_write_read_dt

Menon — Mon, 02 Feb 2026 16:54:16 GMT

Hello,

Thank you for sharing the details. Could you please attach the complete log here, including the error message? Also, which SDK version are you using?

Does this issue occur on the nRF52840 DK, the nRF52840 Feather board, or does it happen on both boards?

Kind regards,
Abhijith

RE: nRF Connect SDK Fundamentals Lesson 6 exercise 1: Error with i2c_write_read_dt

LonnieB — Mon, 02 Feb 2026 14:58:33 GMT

I continued to dig into this problem, and I discovered that if I substitute a write_dt followed by a read_dt for the write_read_dt, I still get an error code of -5 returned, however the actual write and read took place with the read returning a 0x60 as expected. I confirmed this both with my logic analyzer and by printing the "id" returned by the function. So it seems the read and write functions work, but they still return an error code. However the write_read function doesn't return a read value, and it returns an error. Also, further in the example code, the bme_calibrationdata function is called - which in turn calls the i2c_burst_read_dt function. This function returns a -5 error code and like the write_read function does not return any read values (confirmed by me logic analyzer. One further observation: when I build the project with only the main.c file open in the vscode editor, I get no problems. however, I have seen a "problem" when I build with the prj.conf file open in the editor - and the problem is listed as "The I2C drivers must be enabled by CONFIG_I2C to be included in the build". Perhaps this has something to do with some i2c functions working but returning error codes? I have included the prj.conf file in my build configuration. I can include logic analyzer screenshots if requested.