Luckfox Pico Mini B - can't open i2c-3 port from luckfox-config

2025-02-08 4:09

Hello everyone! In Luckfox Pico Mini B, I2C port 3 should be open according to the documentation:

https://wiki.luckfox.com/Luckfox-Pico/L ... -Pico-I2C/

But it is not. I tried to enable I2C using luckfox-config from ADB according to this documentation:

https://wiki.luckfox.com/Luckfox-Pico/L ... ox-config/

I enter I2C menu, select [1] enable, enter speed [100000], but then I get this error:

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Could not find I2C_M_SDA

Please help me enable i2c-3. Thanks in advance!

2025-02-08 6:26

Hello, can you check if there are any pin reuse conflicts? May I ask if you are using Ubuntu or buildroot system?

2025-02-08 16:49

Thank you Ryand,

I'm using buildroot:

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[root@luckfox ]# cat /etc/os-release
NAME=Buildroot
VERSION=-g6a7f87806-dirty
ID=buildroot
VERSION_ID=2023.02.6
PRETTY_NAME="Buildroot 2023.02.6"

I'm not sure how to check for pin conflicts, but PWM pins are disabled:

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[root@luckfox ]# luckfox-config show
/usr/bin/luckfox-config: line 46: warning: command substitution: ignored null byte in input
                                Luckfox_Pico_MiniA/B
                                     + -USB- +
          -               -     VBUS |       | 1V8      -             -
          -               -      GND |       | GND      -             -
          -               -      3V3 |       | GPIO4_C1 - SARADC_M1   -
          - FIQtty_TX     - GPIO1_B2 |       | GPIO4_C0 - SARADC_M0   -
          - FIQtty_RX     - GPIO1_B3 |       | GPIO0_A4 -             - PWM1_M0
 PWM2_M2  - SPI0_M0_CS0   - GPIO1_C0 |       | GPIO1_C7 -             - PWM11_M1
 PWM4_M2  - SPI0_M0_CLK   - GPIO1_C1 |       | GPIO1_C6 -             - PWM10_M1
 PWM5_M2  - SPI0_M0_MOSI  - GPIO1_C2 |       | GPIO1_D3 -             - PWM11_M2
 PWM6_M2  - SPI0_M0_MISO  - GPIO1_C3 |       | GPIO1_D2 -             - PWM0_M1
 PWM8_M1  - UART4_M1_RX   - GPIO1_C4 |       | GPIO1_D1 - UART3_M1_RX - PWM10_M2
 PWM9_M1  - UART4_M1_TX   - GPIO1_C5 |       | GPIO1_D0 - UART3_M1_TX - PWM3_M2
                                     + - + - +

Forgot to mention that right after entering I2C menu I get this message: "No I2C Pins".

2025-02-10 3:59

You need to obtain the latest SDK, the link is as follows: https://github.com/LuckfoxTECH/luckfox-pico. Previously, the mini board did not enable i2C3, but the latest one has

2025-02-15 16:23

Thank you, that worked!

Another question, I'm trying to connect an I2C device that is master, is there are way to set Pico Mini buildroot as slave? When I send I2C data from the attached device the address isn't found, meaning Pico Mini should define its slave address first. But I couldn't find a way to set the slave address in the sample program:

https://drive.google.com/drive/folders/ ... drive_link

2025-02-17 6:19

The i2c controller of rv1106 does not support slave mode. To implement it, only gpio can simulate i2c, and the driver may need to be modified. If there are no special requirements, it is recommended to use SPI. The SPI controller of rv1106 supports both master and slave modes.

2025-02-25 3:26

I want to detect I2C pins level changes, could you please provide an example or direct me to documentation for the RV1103 with Buildroot on how to set GPIO interrupts?

2025-02-27 3:23

Hello, to test the I2C pin level changes, you can use the command set from i2c-tools to assist with testing. For related I2C documentation, please refer to https://wiki.luckfox.com/zh/Luckfox-Pic ... x-Pico-I2C. We do not have examples or documentation for detecting I2C pin level changes through GPIO interrupts. If needed, you can refer to relevant blogs and tutorials. Most Cortex-A platforms use a similar approach for controlling I2C at the application layer.

2026-04-15 9:19

Ryand wrote: ↑2025-02-17 6:19 The i2c controller of rv1106 does not support slave mode. To implement it, only gpio can simulate i2c, and the driver may need to be modified. If there are no special requirements, it is recommended to use SPI. The SPI controller of rv1106 supports both master and slave modes.
企业微信截图_17397728348531.png

Have you found a solution for this issue? If so, could you please share the steps to resolve it?

2026-04-15 10:51

Ryand wrote: ↑2025-02-17 6:19 The i2c controller of rv1106 does not support slave mode. To implement it, only gpio can simulate i2c, and the driver may need to be modified. If there are no special requirements, it is recommended to use SPI. The SPI controller of rv1106 supports both master and slave modes.
企业微信截图_17397728348531.png

I need my Luckfox Pico Max (RV1106) to act as an I2C slave device, but I have been unable to make it work.

Can i set board as slave?

When I run the command to instantiate the slave device, I get the following error:

i2c-slave-eeprom 4-0042: i2c_slave_register: not supported by adapter
i2c-slave-eeprom: probe of 4-0042 failed with error -95

My Questions:
1. Is I2C slave mode officially supported on the Luckfox Pico Max (RV1106)?
2. If yes, what are the correct steps to enable it, and is there a specific kernel configuration or driver patch required?