Demonstrate using the status_led API (#687)

Author: peterharperuk

CMakeLists.txt

@@ -86,6 +86,7 @@ add_subdirectory(pwm)
 add_subdirectory(reset)
 add_subdirectory(rtc)
 add_subdirectory(spi)
+add_subdirectory(status_led)
 add_subdirectory(system)
 add_subdirectory(timer)
 add_subdirectory(uart)

README.md

@@ -371,6 +371,13 @@ App|Description
 [max7219_8x7seg_spi](spi/max7219_8x7seg_spi) | Attaching a Max7219 driving an 8 digit 7 segment display via SPI.
 [max7219_32x8_spi](spi/max7219_32x8_spi) | Attaching a Max7219 driving an 32x8 LED display via SPI.
 
+### Status LED
+
+App|Description
+---|---
+[status_blink](status_led/status_blink) | Blink the onboard LED using the status_led API.
+[color_blink](status_led/color_blink) | Blink the onboard colored (WS2812) LED using the colored_status_led API if supported by the board.
+
 ### System
 
 App|Description

status_led/CMakeLists.txt

@@ -0,0 +1,2 @@
+add_subdirectory(status_blink)
+add_subdirectory(color_blink)

status_led/color_blink/CMakeLists.txt

@@ -0,0 +1,14 @@
+# Blink the colored "status" LED connected to the GPIO defined by PICO_DEFAULT_WS2812_PIN for your board
+add_executable(color_blink
+    color_blink.c
+)
+# You can define PICO_DEFAULT_WS2812_PIN yourself to add a WS2812 led to a normal GPIO
+#target_compile_definitions(color_blink PRIVATE
+#   PICO_DEFAULT_WS2812_PIN=16
+#)
+target_link_libraries(color_blink
+    pico_stdlib
+    pico_status_led
+)
+pico_add_extra_outputs(color_blink)
+example_auto_set_url(color_blink)

status_led/color_blink/color_blink.c

@@ -0,0 +1,35 @@
+/**
+ * Copyright (c) 2025 Raspberry Pi (Trading) Ltd.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include "pico/stdlib.h"
+#include "pico/status_led.h"
+
+#if !PICO_COLORED_STATUS_LED_AVAILABLE
+#warning The color_blink example requires a board with a WS2812 LED
+#endif
+
+#ifndef LED_DELAY_MS
+#define LED_DELAY_MS 250
+#endif
+
+int main() {
+    bool rc = status_led_init();
+    hard_assert(rc);
+    hard_assert(colored_status_led_supported()); // This assert fails if your board does not have WS2812 support
+    uint32_t count = 0;
+    while (true) {
+        // flash red then green then blue
+        uint32_t color = PICO_COLORED_STATUS_LED_COLOR_FROM_RGB(count % 3 == 0 ? 0xaa : 0, count % 3 == 1 ? 0xaa : 0, count % 3 == 2 ? 0xaa : 0);
+        colored_status_led_set_on_with_color(color);
+        count++;
+        sleep_ms(LED_DELAY_MS);
+        assert(colored_status_led_get_state());
+        colored_status_led_set_state(false);
+        sleep_ms(LED_DELAY_MS);
+        assert(!colored_status_led_get_state());
+    }
+    status_led_deinit();
+}

status_led/status_blink/CMakeLists.txt

@@ -0,0 +1,16 @@
+# Blink the "status" LED either connected to the GPIO defined by PICO_DEFAULT_LED_PIN for your board
+# or via the WiFi chip on boards like Pico 2 or Pico 2 W
+
+add_executable(status_blink
+    status_blink.c
+)
+# You can define PICO_DEFAULT_LED_PIN yourself to add a led to a different GPIO
+#target_compile_definitions(status_blink PRIVATE
+#   PICO_DEFAULT_LED_PIN=15
+#)
+target_link_libraries(status_blink
+    pico_stdlib
+    pico_status_led
+)
+pico_add_extra_outputs(status_blink)
+example_auto_set_url(status_blink)

status_led/status_blink/status_blink.c

@@ -0,0 +1,26 @@
+/**
+ * Copyright (c) 2025 Raspberry Pi (Trading) Ltd.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include "pico/stdlib.h"
+#include "pico/status_led.h"
+
+#ifndef LED_DELAY_MS
+#define LED_DELAY_MS 250
+#endif
+
+int main() {
+    bool rc = status_led_init();
+    hard_assert(rc);
+    while (true) {
+        status_led_set_state(true);
+        sleep_ms(LED_DELAY_MS);
+        assert(status_led_get_state());
+        status_led_set_state(false);
+        sleep_ms(LED_DELAY_MS);
+        assert(!status_led_get_state());
+    }
+    status_led_deinit();
+}