I2C Driver Sample Application

Description

The I2C Driver sample application demonstrates board-specific I2C functional validation using the latest standalone example-app build structure.

What this sample does:

  • Initializes I2C and applies the board-specific configuration from hw/<BOARD>/.

  • Runs transfer flows implemented for the selected board defconfig.

  • Verifies transferred bytes and prints match/mismatch results in logs.

On SR110_RDK, the sample supports controller/target communication in both single-board and double-board setups, with blocking or non-blocking transfer modes and controller-transmit or target-transmit directions.

The latest example structure uses a common application source tree with board-specific hardware setup kept under hw/<BOARD>/. For this app:

  • Common application sources such as main.c, i2c_sample_app.c, and i2c_sample_app.h stay in the app root.

  • Application defconfigs are stored under configs/.

  • Board and hardware-specific setup is selected from hw/<BOARD>/, for example hw/SR110_RDK/.

The application can also be exported and built as a standalone app repository. In that flow, keep this app in its own directory, point SRSDK_DIR to the SDK root, and build from the app directory itself. For the full application workflow model, see Astra MCU SDK User Guide.

Supported Boards

  • SR110_RDK

Choose the defconfig that matches your target board, and the build system will pick the corresponding board-specific hardware setup from hw/<BOARD>/.

Prerequisites

Test Case Selection

Before building, choose the testcase defconfig that matches your target board.

You can:

  • Select the required defconfig directly from the application’s configs/ directory.

  • Run make list_defconfigs from the application directory to list all supported defconfigs.

Available defconfigs:

  • sr110_rdk_cm55_i2c_sample_app_double_board_blocking_controller_transmit_defconfig

  • sr110_rdk_cm55_i2c_sample_app_double_board_blocking_target_transmit_defconfig

  • sr110_rdk_cm55_i2c_sample_app_double_board_non_blocking_controller_transmit_defconfig

  • sr110_rdk_cm55_i2c_sample_app_double_board_non_blocking_target_transmit_defconfig

  • sr110_rdk_cm55_i2c_sample_app_single_board_blocking_controller_transmit_defconfig

  • sr110_rdk_cm55_i2c_sample_app_single_board_blocking_target_transmit_defconfig

  • sr110_rdk_cm55_i2c_sample_app_single_board_non_blocking_controller_transmit_defconfig

  • sr110_rdk_cm55_i2c_sample_app_single_board_non_blocking_target_transmit_defconfig

For this app, the default defconfig is:

  • sr110_rdk_cm55_i2c_sample_app_single_board_non_blocking_controller_transmit_defconfig

Connections

SR110_RDK single-board I2C loopback wiring

Connect I2C source pins to I2C target pins on the same board.

RevB:

  • GPIO_15 (I2C_SCL) -> GPIO_44 (I2C_SCL)

  • GPIO_16 (I2C_SDA) -> GPIO_45 (I2C_SDA)

RevC and RevE:

  • GPIO42 (I2C_SCL) -> GPIO_45 (I2C_SCL)

  • GPIO43 (I2C_SDA) -> GPIO_44 (I2C_SDA)

SR110_RDK double-board wiring

Connect between two boards:

  • Board-1 SCL -> Board-2 SCL

  • Board-1 SDA -> Board-2 SDA

  • Board-1 GND -> Board-2 GND

For double-board mode, ensure both GND pins are connected to maintain proper clock synchronization.

Building and Flashing the Example using VS Code

Use the VS Code flow described in the respective platform guide and the VS Code Extension guide:

Build (VS Code):

  1. Select the defconfig that matches your target board and required sample mode.

  2. Open Build and Deploy -> Build Configurations.

  3. Select the i2c_sample_app project configuration in the Project Configuration dropdown.

  4. If you need to adjust SR110-specific I2C mode options, use the extension’s configuration flow or menuconfig before building.

  5. Build with Build (SDK+Project) for the first build, or Build (Project) for rebuilds.

Flash (VS Code):

  1. Use Image Conversion to generate the flash image.

  2. Use Image Flashing (SWD/JTAG) to flash the firmware image.

Building and Flashing the Example using CLI

Use the CLI flow described in the respective platform guide:

Build (CLI):

  1. Build from the application directory itself:

    cd <sdk-root>/examples/driver_examples/i2c_sample_app
export SRSDK_DIR=<sdk-root>
make <app_defconfig> BUILD=SRSDK

  2. If you need to update SR110 application mode settings, apply the defconfig without building and then open menuconfig:

    cd <sdk-root>/examples/driver_examples/i2c_sample_app
export SRSDK_DIR=<sdk-root>
make <app_defconfig> BUILD=NONE
make menuconfig

  3. For faster rebuilds when only app code changes, reuse the app-local installed SDK package:

    cd <sdk-root>/examples/driver_examples/i2c_sample_app
export SRSDK_DIR=<sdk-root>
make build

  4. If this app has been exported to its own repository, use the same commands from that exported app directory after setting SRSDK_DIR to the SDK root.

Build outputs (CLI):

  • Application binary: <app-dir>/out/<target>/release/<target>.elf

  • App-local SDK package: <app-dir>/install/<BOARD>/<BUILD_TYPE>/

Flash (CLI):

Flash SR110

  1. Activate the SDK venv (required for image generation tools):

    # Linux/macOS
source <sdk-root>/.venv/bin/activate
# Windows PowerShell
.\.venv\Scripts\Activate.ps1

  2. Generate the flash image:

    cd <sdk-root>/tools/srsdk_image_generator
python srsdk_image_generator.py \
  -B0 \
  -flash_image \
  -sdk_secured \
  -spk "<sdk-root>/tools/srsdk_image_generator/Inputs/spk_rc4_1_0_secure_otpk.bin" \
  -apbl "<sdk-root>/tools/srsdk_image_generator/Inputs/sr100_b0_bootloader_ver_0x012F_ASIC.axf" \
  -m55_image "<sdk-root>/examples/driver_examples/i2c_sample_app/out/sr110_cm55_fw/release/sr110_cm55_fw.elf" \
  -flash_type "GD25LE128" \
  -flash_freq "67"

  3. Flash the firmware image:

    cd <sdk-root>
python tools/openocd/scripts/flash_xspi_tcl.py \
  --cfg_path tools/openocd/configs/sr110_m55.cfg \
  --image tools/srsdk_image_generator/Output/B0_Flash/B0_flash_full_image_GD25LE128_67Mhz_secured.bin \
  --erase-all

Flash SL2610

  1. Build the SL2610 bootloader image.

    cd <sdk-root>
export SRSDK_DIR=<sdk-root>
make <SL2610_Bootloader_defconfig> BOARD=<BOARD>
make astrasdk

  2. Generate the system sub-image.

    cd <sdk-root>/examples/driver_examples/i2c_sample_app
export SRSDK_DIR=<sdk-root>
make imagegen

  3. Flash or download the image using the SL2610 workflow.

    Refer: SL2610 Build and Flash with CLI

Running the Application using VS Code Extension

  1. Complete the required board wiring from the Connections section.

  2. Flash the image and press RESET on the board.

  3. For SR110_RDK logging output, click SERIAL MONITOR and connect to the DAP logger port on J14.

    • To make it easier to identify, ensure only J14 is plugged in (not J13).

    • The logger port is not guaranteed to be consistent across OSes. As a starting point:

      • Windows: try the lower-numbered J14 COM port first.

      • Linux/macOS: try the higher-numbered J14 port first.

    • If you do not see logs after a reset, switch to the other J14 port.

  4. Observe I2C configuration logs, transfer completion logs, and match/mismatch results.

SR110_RDK double-board run note

  • Build and flash controller-mode image to one board and target-mode image to the other board.

  • Reset both boards after wiring is complete.

Expected Logs (SR110_RDK example)

Controller Write

0001666732:[0][WRN][LOGR]:Changing logger interface to LOGGER_IF_CONSOLE
0001781732:[0][INF][SYS ]:Application drivers
initialization complete without errors.
0001883107:[0][INF][SYS ]:SR110 SDK version 1.3.0
0001996986:[0][INF][GENR]:Starting I2C sample app...Target task started
0002101861:[0][INF][GENR]:Controller task started
0002204249:[0][DBG][GENR]:running task for loop 0x3000dfe0
0002305735:[0][INF][USB ]:USB Device Driver task
0002403497:[0][INF][USB ]:USB device unmounted
0002506487:[0][INF][USB ]:USB stopped
0003957107:[0][INF][GENR]:ten_bit_addr: 0,general_call_response:0,scl_stuck_timeout_ms:1,            sda_stuck_timeout_ms:1,target_address:50
0003957107:[0][INF][GENR]:0004121774:[0Target: Readi0004121855:[0][INF][GENR]:Controller target address: 0x32
0004222018:[0][INF][GENR]:Semaphore successfully taken
0004322121:[0][INF][GENR]:Controller: Sending data...
0005560586:[0][INF][GENR]:Write is completed
0005714488:[0][INF][GENR]:[Controller] I2C Event: 0x0
0005818112:[0][INF][GENR]:[Controller] I2C Event: 0x4
0005920614:[0][INF][GENR]:[Target] I2C Event: 0x1
0006029112:[0][INF][GENR]:[Target] I2C Event: 0x4
0006139512:[0][INF][GENR]:0006139512:[0][INF][GENR]:CTarget: Data received:RX[0] = 0x02
0006253498:[0][INF][GENR]:RX[1] = 0x01
0006356015:[0][INF][GENR]:0006356015:[00006356088:[0][INF][GENR]:RX[3] = 0x04
0006455873:[0][INF][GENR]:RX[4] = 0x05
0006568502:[0][INF][GENR]:RX[5] = 0x06
0006672998:[0][INF][GENR]:RX[6] = 0x07
0006778623:[0][INF][GENR]:RX[7] = 0x08
0006879748:[0][INF][GENR]:RX[8] = 0x29
0006985495:[0][INF][GENR]:RX[9] = 0x30
0007086498:[0][INF][GENR]:RX[10] = 0x31
0007185623:[0][INF][GENR]:RX[11] = 0x32
0007301771:[0][INF][HAPI]

Target Write

0001688861:[0][WRN][LOGR]:Changing logger interface to LOGGER_IF_CONSOLE
0001805737:[0][INF][SYS ]:Application drivers
initialization complete without errors
0001919612:[0][INF][SYS ]:SR110 SDK version 1.3.0
0002022116:[0][INF][GENR]:Starting I2C sample app...Target task started
0002129116:[0][INF][GENR]:Controller task started
0002238504:[0][DBG][GENR]:running task for loop 0x3000dfd8
0002353365:[0][INF][USB ]:USB Device Driver task
0002455627:[0][INF][USB ]:USB device unmounted
0002559117:[0][INF][USB ]:USB stopped
0005172865:[0][INF][GENR]:ten_bit_addr: 0,general_call_response:0,scl_stuck_timeout_ms:1,            sda_stuck_timeout_ms:1,target_address:50
0005172865:[0][INF][GENR]:ten_bit_addr: 0,enable_bus_clear:0,clear_stuck_sda:0,            scl_stuck_timeout_ms:1,sda_stuck_timeout_ms:1
0005430377:[0][INF][GENR]:Controller target address: 0x32
0006842213:[0][INF][GENR]:Semaphore successfully takenController: Reading starts...
0006921782:[0][INF][HAPI]:------------------------------------------
0007024131:[0][INF][HAPI]:       Host API Router task
0007125747:[0][INF][GENR]:[Controller] I2C Event: 0x1

0007338743:[0][INF][GENR]:[Target] I2C Event: 0x0
0007438867:[0][INF][GENR]:[Target] I2C Event: 0x4
0007541752:[0][INF][HAPI]:------------------------------------------
0007642253:[0][INF][HAPI]:Active interface is USB
0007753269:[0][INF][GENR]:0007753269:[0][INF][GENR]:CNon-Blocking read success with event type: 1
Non-Blocking read success with event type: 1
0Read byte [0]: 0x02
0007962151:[0][INF][GENR]:Non-Blocking target write with event type: 4
00008177285:[0][INF][GENR]:Read byte [2]: 0x03
0008275380:[0][INF][GENR]:Read byte [3]: 0x04
0008377005:[0][INF][GENR]:Read byte [4]: 0x05
0008477754:[0][INF][GENR]:Read byte [5]: 0x06
0008587879:[0][INF][GENR]:Read byte [6]: 0x07
0008693879:[0][INF][GENR]:Read byte [7]: 0x08
0008803505:[0][INF][GENR]:Read byte [8]: 0x29
0008905379:[0][INF][GENR]:Read byte [9]: 0x30
0009009379:[0][INF][GENR]:Read byte [10]: 0x31
0009122755:[0][INF][GENR]:Read byte [11]: 0x32