I2S Driver Sample Application

Description

The I2S Driver sample application demonstrates I2S audio data transfer on the supported boards for this application. It performs end-to-end I2S validation including transmit, receive, loopback, dual-board communication, and DMA-driven buffering.

The sample includes multiple I2S verification modes:

  • Single-board loopback: Asynchronous TX with RX loopback on the same board.

  • Dual TX node: Transmit-only node for dual-board testing.

  • Dual RX node: Receive-only node with integrity validation.

  • Dual RX replay: Capture on RX and replay the captured data on TX.

During each run, the app logs initialization status, configuration details, DMA rate/IRQ stats, and validation results. This makes it easy for end users to confirm that I2S setup and data flow are working as expected.

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, i2s_sample_app.c, and i2s_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/SL2610_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

This application supports:

  • SL2610_RDK

Select the defconfig that matches your target board and the desired I2S mode, 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 both your target board and the I2S mode you want to validate.

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 I2S defconfigs (SL2610 RDK):

  • sl2610_rdk_cm52_i2s_sample_app_single_board_loopback_defconfig: Async TX with RX loopback on a single board.

  • sl2610_rdk_cm52_i2s_sample_app_dual_tx_defconfig: Dual-board TX node image.

  • sl2610_rdk_cm52_i2s_sample_app_dual_rx_defconfig: Dual-board RX node image.

  • sl2610_rdk_cm52_i2s_sample_app_dual_rx_replay_defconfig: Dual-board RX capture with TX replay.

For this app, the default defconfig is:

  • sl2610_rdk_cm52_i2s_sample_app_single_board_loopback_defconfig

Building and Flashing the Example using VS Code

Use the VS Code flow described in the respective soc vscode guides and the VS Code Extension guide:

Build (VS Code):

  1. Open Build and Deploy -> Build Configurations.

  2. Select the i2s_sample_app project configuration in the Project Configuration dropdown.

  3. Select the required defconfig for the I2S mode you want to validate.

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

Flash (VS Code):

  1. Use the SL2610 image-generation flow to generate the required sub-image.

  2. Open Image Flashing (SL2610).

  3. Select Flash Target as M52 Image.

  4. In Image Path, browse to and select the generated sub-image file, such as sysmgr.subimg.gz.

  5. Start the flashing operation to program the image to the target.

Building and Flashing the Example using CLI

Use the CLI flow described in the respective build guide:

Build (CLI):

  1. Build from the application directory itself:

    cd <sdk-root>/examples/driver_examples/i2s_sample_app
export SRSDK_DIR=<sdk-root>
make <app_defconfig> BUILD=SRSDK

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

    cd <sdk-root>/examples/driver_examples/i2s_sample_app
export SRSDK_DIR=<sdk-root>
make build

  3. 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 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/i2s_sample_app
export SRSDK_DIR=<sdk-root>
make imagegen

  3. Flash/download image to target.

    Refer: SL2610 Platform Guide

Running the Application using VS Code Extension

  1. Press RESET on the board after flashing.

  2. For 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.

  3. For I2S signal observation, connect a logic analyzer to the I2S pins used by your board.

  4. I2S sample logs appear in the logger window, including transfer progress and validation results.

Expected Logs

Single board loopback:

0000000000:[0][WRN][LOGR]:Changing logger interface to LOGGER_IF_UART_0
0000000000:[0][INF][SYS ]:M52:: Build Date 07-04-2026 Time 07:28:29 Commit 727d936b
0000000000:[0][INF][SYS ]:sl2610 SDK version 1.3.0
0000000000:[0][INF][I2S ]:I2S Sample App Starts
0000000004:[0][INF][I2S ]:Mode: SINGLE board ASYNC TX with RX loopback
0000000010:[0][DBG][I2S ]:[I2S][APP_TX] soc_addr=0xe1006854 bytes=3840
0000000017:[0][INF][I2S ]:[I2S][DHUB_RATE] start: period_frames=480 expected_irq/s=100 repeat=0
0000000225:[0][INF][I2S ]:loopback done: pass=10 fail=0 tx_buf_cb=20 rx_buf_cb=10
0000000232:[0][INF][I2S ]:I2S Sample App End

Dual TX:

0000000000:[0][WRN][LOGR]:Changing logger interface to LOGGER_IF_UART_0
0000000000:[0][INF][SYS ]:M52:: Build Date 07-04-2026 Time 07:35:38 Commit 727d936b
0000000000:[0][INF][SYS ]:sl2610 SDK version 1.3.0
0000000000:[0][INF][I2S ]:I2S Sample App Starts
0000000004:[0][INF][I2S ]:Mode: DUAL board TX node
0000000008:[0][DBG][I2S ]:[I2S][APP_TX] soc_addr=0xe1006854 bytes=3840
0000000015:[0][INF][I2S ]:[I2S][DHUB_RATE] start: period_frames=480 expected_irq/s=100 repeat=0
0000001024:[0][INF][I2S ]:[I2S][DHUB_RATE] cmd/s=101 irq/s=100 irq_per_cmd=0.990 window_ms=1009 expected_irq/s=100
0000002027:[0][INF][I2S ]:[I2S][DHUB_RATE] cmd/s=100 irq/s=100 irq_per_cmd=1.000 window_ms=1003 expected_irq/s=100
0000003030:[0][INF][I2S ]:[I2S][DHUB_RATE] cmd/s=100 irq/s=100 irq_per_cmd=1.000 window_ms=1003 expected_irq/s=100
0000004032:[0][INF][I2S ]:[I2S][DHUB_RATE] cmd/s=100 irq/s=100 irq_per_cmd=1.000 window_ms=1002 expected_irq/s=100
0000006023:[0][INF][I2S ]:DUAL board TX complete, tx_complete_irq_count=481
0000006029:[0][INF][I2S ]:I2S Sample App End

DUAL RX:

0000000000:[0][WRN][LOGR]:Changing logger interface to LOGGER_IF_UART_0
0000000000:[0][INF][SYS ]:M52:: Build Date 07-04-2026 Time 07:44:51 Commit 727d936b
0000000000:[0][INF][SYS ]:sl2610 SDK version 1.3.0
0000000000:[0][INF][I2S ]:I2S Sample App Starts
0000000004:[0][INF][I2S ]:Mode: DUAL board RX node
0000000028:[0][INF][I2S ]:DUAL board RX integrity PASS (start=0 offset=35)
0000000034:[0][INF][I2S ]:I2S Sample App End

DUAL RX Replay:

0000000000:[0][WRN][LOGR]:Changing logger interface to LOGGER_IF_UART_0
0000000000:[0][INF][SYS ]:M52:: Build Date 07-04-2026 Time 07:38:53 Commit 727d936b
0000000000:[0][INF][SYS ]:sl2610 SDK version 1.3.0
0000000000:[0][INF][I2S ]:I2S Sample App Starts
0000000004:[0][INF][I2S ]:Mode: DUAL board RX node + TX replay (all IRQ)
0000000012:[0][INF][I2S ]:Starting RX capture for replay...
0000020987:[0][INF][I2S ]:Connect it with DAC
0000050991:[0][INF][GENR]:Starting TX replay...
0000050995:[0][INF][I2S ]:TX replay block_size=3840 bytes (pattern=3840 bytes)
0000051002:[0][DBG][I2S ]:[I2S][APP_TX] soc_addr=0xe1007754 bytes=3840
0000051008:[0][INF][I2S ]:[I2S][DHUB_RATE] start: period_frames=480 expected_irq/s=100 repeat=0
0000051017:[0][INF][I2S ]:Post start: TX state=2 tx_irq=1 rx_irq=1 err=0 waited=0msDUAL RX replay TX complete
0000051026:[0][INF][I2S ]:I2S Sample App End