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--- zephyr [2025/04/20 08:36] – [Devicetree] utedass
+++ zephyr [2025/12/03 21:35] (current) – [Länkar] utedass
@@ Line 4: / Line 4: @@
 ===== Länkar =====
+  * [[https://github.com/Utedass/zephyr-workspace]] -- My own devcontainer setup for Zephyr development
   * [[https://embedded.fm/episodes/475?rq=zephyr]] -- Nämner bland annat att det finns några tänkta sätt att strukturera sina projekt för att inte blanda in sin projekt-kod i zephyr-repot
+  * [[https://www.youtube.com/watch?v=tAH5fy0rSo4|Youtube Linux Foundation]] -- Zephyr Project: RTOS Start-up and Initialization Flow
+  * [[https://interrupt.memfault.com/blog/building-drivers-on-zephyr]]
+  * [[https://community.circuitdojo.com/d/146-zephyr-driver-development-use-of-i2c-and-spi-apis]]
+== Real world examples ==
+  * [[https://github.com/zephyrproject-rtos/awesome-zephyr-rtos/tree/main]] -- Awezome Zephyr related list
+  * [[https://github.com/xycloo/zephyr-examples/tree/master]] -- Rust examples
+  * [[https://github.com/zmkfirmware/zmk/tree/main]] -- Zephyr Mechanical Keyboard
+  * [[https://github.com/jakkra/ZSWatch/tree/main]] -- Open Source Smart Watch
 == Shawn Hymel / Digikey ==
@@ Line 40: / Line 53: @@
 <code>
 python -m esptool --port COM19 --chip auto --baud 921600 --before default_reset --after hard_reset write_flash -u --flash_size detect 0x0 .\build\zephyr\zephyr.bin
+</code>
+===== Platser =====
+| ''zephyr/dts/<arch>/<mfr>/<soc>/'' | .dtsi filer för olika chip |
+| ''zephyr/dts/bindings/<feature>/<compatible>.yaml'' | .yaml binding-filer för olika chips drivrutiner |
+| ''zephyr/boards/<mfr>/<board>/'' | .dts, Kconfig och default configs för boards |
+| ''zephyr/soc/<mfr>/<soc>/soc.h'' | Startup-kod, HAL-includes etc för specifikt chip |
+| ''zephyr/arch/<arch>/core/'' | Assembler-startup etc för specifik arkitektur |
+===== CMake =====
+=== CMakeList.txt in project ===
+<code cmake>
+cmake_minimum_required(VERSION 3.20.0)
+# Optional for your own extra KConfig modules
+set(ZEPHYR_EXTRA_MODULES "${CMAKE_SOURCE_DIR}/../../modules/say_hello")
+# Mandatory thing
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+# Name your project
+project(random)
+# Adds your main entry point to the Zephyr-created "app" lib
+target_sources(app PRIVATE src/main.c)
+</code>
+=== CMakeLists.txt ===
+CMakeLists file for your own modules
+<code cmake>
+# Check if SAY_HELLO is set in Kconfig
+if(CONFIG_SAY_HELLO)
+    # Add your include directory
+    zephyr_include_directories(.)
+    # Add the source file you want to compile
+    zephyr_library_sources(say_hello.c)
+endif()
 </code>
@@ Line 50: / Line 104: @@
 </code>
-Sparas till ./build/zephyr/.config som kommer tas bort vid nästa bygge.
+Sparas till ''./build/zephyr/.config'' som kommer tas bort vid nästa bygge.
+Generates an include file in ''build/zephyr/include/generated/zephyr/autoconf.h''
 För att göra persistent, kolla diff mellan ./build/zephyr/.config.old
@@ Line 86: / Line 142: @@
 </code>
+==== Egna moduler ====
+För att lägga till egna moduler som går att aktivera i menuconfig, lägg in en fil som heter exempelvis KConfig i modulens mapp.
+<code>
+# Create a new option in menuconfig
+config SAY_HELLO
+    bool "Basic print test to console"
+    default n   # Set the library to be disabled by default
+    depends on PRINTK   # Make it dependent on PRINTK
+    help
+        Adds say_hello() function to print a basic message to the console.
+</code>
+Lägg även till en mapp som heter exakt ''zephyr'' i modulens mapp. Lägg in en fil som heter exakt  ''module.yaml'' med likande innehåll. kconfig: pekar ut KConfig-filen ovan.
+<code yaml>
+name: say_hello
+build:
+  cmake: .
+  kconfig: Kconfig
+</code>
 ===== Devicetree =====
@@ Line 91: / Line 168: @@
   * [[https://docs.zephyrproject.org/3.7.0/build/dts/index.html|Zephyr DTS page]]
   * [[https://docs.zephyrproject.org/3.7.0/build/dts/bindings-syntax.html|Zephyr DTS bindings]]
+The final devicetree will end up under ''build/zephyr/zephyr.dts''.
+There is an include file generated from this in ''build/zephyr/include/generated/zephyr/devicetree_generated.h''
 === Words ===
@@ Line 113: / Line 194: @@
 [[https://docs.zephyrproject.org/3.7.0/build/dts/intro-syntax-structure.html|Zephyr DTS Syntax Structure]]
-From file ''/opt/toolchains/zephyr/dts/xtensa/espressif/esp32s3/esp32s3_common.dtsi'' there is a part defining the alias ''gpio0'' for the path ''/soc/gpio/gpio@60004000''.
+In the boards folder for esp32s3_devkitc there is a DTS file for the appcpu, ''/opt/toolchains/zephyr/boards/espressif/esp32s3_devkitc/esp32s3_devkitc_appcpu.dts''.
+<code>
+/*
+ * Copyright (c) 2024 Espressif Systems (Shanghai) Co., Ltd.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+/dts-v1/;
+#include <espressif/esp32s3/esp32s3_appcpu.dtsi>
+#include <espressif/partitions_0x0_amp.dtsi>
+/ {
+	model = "Espressif ESP32S3-DevkitC APPCPU";
+	compatible = "espressif,esp32s3";
+	chosen {
+		zephyr,sram = &sram0;
+		zephyr,ipc_shm = &shm0;
+		zephyr,ipc = &ipm0;
+	};
+};
+&trng0 {
+	status = "okay";
+};
+&ipm0 {
+	status = "okay";
+};
+</code>
+This ''#include <espressif/esp32s3/esp32s3_appcpu.dtsi>'' includes a devicetree source include-file which in turn includes  ''#include "esp32s3_common.dtsi"''.
+Int the file ''/opt/toolchains/zephyr/dts/xtensa/espressif/esp32s3/esp32s3_common.dtsi'' there is a part defining the alias ''gpio0'' for the path ''/soc/gpio/gpio@60004000''.
 <code>
 			gpio0: gpio@60004000 {
@@ Line 155: / Line 271: @@
   - flags
 </code>
+Also at the location for the board files is the ''/opt/toolchains/zephyr/boards/espressif/esp32s3_devkitc/esp32s3_devkitc-pinctrl.dtsi'' device tree source include file. The start of the file looks like this:
+<code>
+/*
+ * Copyright (c) 2024 Espressif Systems (Shanghai) Co., Ltd.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <zephyr/dt-bindings/pinctrl/esp-pinctrl-common.h>
+#include <dt-bindings/pinctrl/esp32s3-pinctrl.h>
+#include <zephyr/dt-bindings/pinctrl/esp32s3-gpio-sigmap.h>
+&pinctrl {
+	uart0_default: uart0_default {
+		group1 {
+			pinmux = <UART0_TX_GPIO43>;
+			output-high;
+		};
+		group2 {
+			pinmux = <UART0_RX_GPIO44>;
+			bias-pull-up;
+		};
+	};
+	i2c0_default: i2c0_default {
+		group1 {
+			pinmux = <I2C0_SDA_GPIO1>,
+				 <I2C0_SCL_GPIO2>;
+			bias-pull-up;
+			drive-open-drain;
+			output-high;
+		};
+	};
+</code>
+The line ''#include <dt-bindings/pinctrl/esp32s3-pinctrl.h>'' refers to the file ''/opt/toolchains/zephyr/include/zephyr/dt-bindings/pinctrl/esp32s3-pinctrl.h'' which has a lot of defines used in the device tree include file.
+<code>
+#define UART0_TX_GPIO43 ESP32_PINMUX(43, ESP_NOSIG, ESP_U0TXD_OUT)
+</code>
+All of the files in ''/opt/toolchains/zephyr'' directories are default files and the device tree thingies can be overridden in you project with a overlay-file.
 === Lables, names, property names ===
@@ Line 187: / Line 347: @@
 </code>
+==== Overlay files ====
+== Example ==
+''boards/esp32s3_devkitc.overlay''
+<code>
+/ {
+    aliases {
+        my-led = &led0;
+    };
+    leds {
+        compatible = "gpio-leds";
+        led0: d5 {
+            gpios = <&gpio0 5 GPIO_ACTIVE_HIGH>;
+        };
+    };
+};
+</code>
+===== C-kod =====
+== Exempel blink ==
+<code c>
+#include <stdio.h>
+#include <zephyr/kernel.h>
+#include <zephyr/drivers/gpio.h>
+// Settings
+static const int32_t sleep_time_ms = 1000;
+static const struct gpio_dt_spec led = GPIO_DT_SPEC_GET(DT_ALIAS(my_led), gpios);
+int main(void)
+{
+	int ret;
+	int state = 0;
+	// Make sure that the GPIO was initialized
+	if (!gpio_is_ready_dt(&led))
+	{
+		return 0;
+	}
+	// Set the GPIO as output
+	ret = gpio_pin_configure_dt(&led, GPIO_OUTPUT);
+	if (ret < 0)
+	{
+		return 0;
+	}
+	// Do forever
+	while (1)
+	{
+		// Change the state of the pin and print
+		state = !state;
+		printk("LED state: %d\r\n", state);
+		// Set pin state
+		ret = gpio_pin_set_dt(&led, state);
+		if (ret < 0)
+		{
+			return 0;
+		}
+		// Sleep
+		k_msleep(sleep_time_ms);
+	}
+	return 0;
+}
+</code>