samples: peripheral: add PWM sample

doc/nrf-bm/release_notes/release_notes_changelog.rst

@@ -65,7 +65,7 @@ No changes since the latest nRF Connect SDK Bare Metal release.
 Peripheral samples
 ------------------
 
-No changes since the latest nRF Connect SDK Bare Metal release.
+* Added the :ref:`pwm_sample` sample.
 
 DFU samples
 -----------

samples/peripherals/pwm/CMakeLists.txt

@@ -0,0 +1,12 @@
+#
+# Copyright (c) 2025 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+cmake_minimum_required(VERSION 3.20.0)
+
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(pwm)
+
+target_sources(app PRIVATE src/main.c)

samples/peripherals/pwm/Kconfig

@@ -0,0 +1,34 @@
+#
+# Copyright (c) 2025 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+menu "PWM sample"
+
+config PWM_IRQ_PRIO
+	int "PWM IRQ priority"
+	default 5
+
+config PWM_PLAYBACK_COUNT
+	int "PWM playback count"
+	default 1
+	help
+	  Number of times the sequence will be replayed until the
+	  NRFX_PWM_EVT_FINISHED event is raised.
+
+config PWM_VALUE_REPEATS
+	int "PWM value repeats"
+	default 150
+	help
+	   Number of times that each duty cycle is to be repeated (after being played once).
+
+
+module=PWM_SAMPLE
+module-dep=LOG
+module-str=PWM Sample
+source "$(ZEPHYR_BASE)/subsys/logging/Kconfig.template.log_config"
+
+endmenu # "PWM sample"
+
+source "Kconfig.zephyr"

samples/peripherals/pwm/README.rst

@@ -0,0 +1,96 @@
+.. _pwm_sample:
+
+PWM
+###
+
+.. contents::
+   :local:
+   :depth: 2
+
+The PWM sample demonstrates how to configure and use PWM with |BMlong|.
+
+Requirements
+************
+
+The sample supports the following development kits:
+
+.. tabs::
+
+   .. group-tab:: Simple board variants
+
+      The following board variants do **not** have DFU capabilities.
+
+      .. list-table::
+         :header-rows: 1
+
+         * - Hardware platform
+           - PCA
+           - SoftDevice
+           - Board target
+         * - `nRF54L15 DK`_
+           - PCA10156
+           - S115
+           - bm_nrf54l15dk/nrf54l15/cpuapp/s115_softdevice
+         * - `nRF54L15 DK`_ (emulating nRF54L10)
+           - PCA10156
+           - S115
+           - bm_nrf54l15dk/nrf54l10/cpuapp/s115_softdevice
+         * - `nRF54L15 DK`_ (emulating nRF54L05)
+           - PCA10156
+           - S115
+           - bm_nrf54l15dk/nrf54l05/cpuapp/s115_softdevice
+
+   .. group-tab:: MCUboot board variants
+
+      The following board variants have DFU capabilities.
+
+      .. list-table::
+         :header-rows: 1
+
+         * - Hardware platform
+           - PCA
+           - SoftDevice
+           - Board target
+         * - `nRF54L15 DK`_
+           - PCA10156
+           - S115
+           - bm_nrf54l15dk/nrf54l15/cpuapp/s115_softdevice/mcuboot
+         * - `nRF54L15 DK`_ (emulating nRF54L10)
+           - PCA10156
+           - S115
+           - bm_nrf54l15dk/nrf54l10/cpuapp/s115_softdevice/mcuboot
+         * - `nRF54L15 DK`_ (emulating nRF54L05)
+           - PCA10156
+           - S115
+           - bm_nrf54l15dk/nrf54l05/cpuapp/s115_softdevice/mcuboot
+
+Overview
+********
+
+The sample initializes a PWM instance that blinks LED1 and LED3 on the device.
+
+.. note::
+
+  The PWM signal can be exposed only on GPIO pins that belong to the same domain as the target pin.
+  For nRF54L-series there is only one domain which contains both PWM and GPIO: PWM20/21/22 and GPIO Port P1.
+  For the nRF54L Series only LEDs connected to P1 can work with PWM,  for the nRF54L15DK this is LED1 and LED3.
+
+Building and running
+********************
+
+This sample can be found under :file:`samples/peripherals/pwm/` in the |BMshort| folder structure.
+
+.. include:: /includes/create_sample.txt
+
+.. include:: /includes/configure_and_build_sample.txt
+
+.. include:: /includes/program_sample.txt
+
+Testing
+=======
+
+You can test this sample by performing the following steps:
+
+1. Compile and program the application.
+#. Observe that the ``PWM sample started`` message is printed.
+#. Observe that LED1 and LED3 are blinking.

samples/peripherals/pwm/prj.conf

@@ -0,0 +1,2 @@
+CONFIG_LOG=y
+CONFIG_LOG_BACKEND_BM_UARTE=y

samples/peripherals/pwm/sample.yaml

@@ -0,0 +1,21 @@
+sample:
+  name: PWM Sample
+tests:
+  sample.pwm:
+    sysbuild: true
+    build_only: true
+    integration_platforms:
+      - bm_nrf54l15dk/nrf54l05/cpuapp/s115_softdevice
+      - bm_nrf54l15dk/nrf54l10/cpuapp/s115_softdevice
+      - bm_nrf54l15dk/nrf54l15/cpuapp/s115_softdevice
+      - bm_nrf54l15dk/nrf54l05/cpuapp/s115_softdevice/mcuboot
+      - bm_nrf54l15dk/nrf54l10/cpuapp/s115_softdevice/mcuboot
+      - bm_nrf54l15dk/nrf54l15/cpuapp/s115_softdevice/mcuboot
+    platform_allow:
+      - bm_nrf54l15dk/nrf54l05/cpuapp/s115_softdevice
+      - bm_nrf54l15dk/nrf54l10/cpuapp/s115_softdevice
+      - bm_nrf54l15dk/nrf54l15/cpuapp/s115_softdevice
+      - bm_nrf54l15dk/nrf54l05/cpuapp/s115_softdevice/mcuboot
+      - bm_nrf54l15dk/nrf54l10/cpuapp/s115_softdevice/mcuboot
+      - bm_nrf54l15dk/nrf54l15/cpuapp/s115_softdevice/mcuboot
+    tags: ci_build

samples/peripherals/pwm/src/main.c

@@ -0,0 +1,78 @@
+/*
+ * Copyright (c) 2025 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+#include <zephyr/logging/log.h>
+#include <zephyr/logging/log_ctrl.h>
+#include <nrfx_pwm.h>
+#include <board-config.h>
+
+LOG_MODULE_REGISTER(app, CONFIG_PWM_SAMPLE_LOG_LEVEL);
+
+#define PWM_INST_IDX 20
+
+nrf_pwm_values_common_t pwm_val[] = {
+	0, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000,
+	900, 800, 700, 600, 500, 400, 300, 200, 100, 0
+};
+
+static void pwm_handler(nrfx_pwm_evt_type_t event_type, void *ctx)
+{
+	static uint32_t curr_loop = 1;
+
+	LOG_INF("Loops: %u ", curr_loop);
+	curr_loop++;
+}
+
+int main(void)
+{
+	nrfx_err_t err;
+	nrfx_pwm_t pwm_instance = NRFX_PWM_INSTANCE(PWM_INST_IDX);
+	/*
+	 * PWM signal can be exposed on GPIO pin only within same domain.
+	 * For nRF54L-series there is only one domain which contains both PWM and GPIO:
+	 * PWM20/21/22 and GPIO Port P1.
+	 * Only LEDs connected to P1 can work with PWM, in this case LED1 and LED3.
+	 */
+	nrfx_pwm_config_t config = NRFX_PWM_DEFAULT_CONFIG(BOARD_PIN_LED_1, BOARD_PIN_LED_3,
+							   NRF_PWM_PIN_NOT_CONNECTED,
+							   NRF_PWM_PIN_NOT_CONNECTED);
+	nrf_pwm_sequence_t seq = {
+		.values = {pwm_val},
+		.length = NRFX_ARRAY_SIZE(pwm_val),
+		.repeats = CONFIG_PWM_VALUE_REPEATS,
+		.end_delay = 0
+	};
+
+	LOG_INF("PWM sample started");
+
+	IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_PWM_INST_GET(PWM_INST_IDX)),
+		    CONFIG_PWM_IRQ_PRIO, NRFX_PWM_INST_HANDLER_GET(20), 0, 0);
+
+	err = nrfx_pwm_init(&pwm_instance, &config, pwm_handler, &pwm_instance);
+	if (err != NRFX_SUCCESS) {
+		LOG_ERR("Failed to initialize PWM, nrfx_error %#x", err);
+		goto idle;
+	}
+
+	nrfx_pwm_simple_playback(&pwm_instance, &seq, CONFIG_PWM_PLAYBACK_COUNT,
+				 NRFX_PWM_FLAG_LOOP);
+
+idle:
+	while (true) {
+		while (LOG_PROCESS()) {
+		}
+
+		/* Wait for an event. */
+		__WFE();
+
+		/* Clear Event Register */
+		__SEV();
+		__WFE();
+
+	}
+
+	return 0;
+}