From f67b58493c2486a1229fb94de533ce79ad4bd7d4 Mon Sep 17 00:00:00 2001
From: Devoalda <linuxes_mojoworld@aleeas.com>
Date: Sun, 17 Sep 2023 22:48:14 +0800
Subject: [PATCH] Base Lab 4 Donw

---
 lab_4/CMakeLists.txt | 49 ++++++++++++++++++++++++++++++
 lab_4/lab_4.c        | 72 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 121 insertions(+)
 create mode 100644 lab_4/CMakeLists.txt
 create mode 100644 lab_4/lab_4.c

diff --git a/lab_4/CMakeLists.txt b/lab_4/CMakeLists.txt
new file mode 100644
index 0000000..4bdb304
--- /dev/null
+++ b/lab_4/CMakeLists.txt
@@ -0,0 +1,49 @@
+# Generated Cmake Pico project file
+
+cmake_minimum_required(VERSION 3.13)
+
+set(CMAKE_C_STANDARD 11)
+set(CMAKE_CXX_STANDARD 17)
+
+set(PICO_BOARD pico_w CACHE STRING "Board type")
+
+# Pull in Raspberry Pi Pico SDK (must be before project)
+include(pico_sdk_import.cmake)
+
+if (PICO_SDK_VERSION_STRING VERSION_LESS "1.4.0")
+  message(FATAL_ERROR "Raspberry Pi Pico SDK version 1.4.0 (or later) required. Your version is ${PICO_SDK_VERSION_STRING}")
+endif()
+
+project(lab_4 C CXX ASM)
+
+# Initialise the Raspberry Pi Pico SDK
+pico_sdk_init()
+
+# Add executable. Default name is the project name, version 0.1
+
+add_executable(lab_4 lab_4.c )
+
+pico_set_program_name(lab_4 "lab_4")
+pico_set_program_version(lab_4 "0.1")
+
+pico_enable_stdio_uart(lab_4 1)
+pico_enable_stdio_usb(lab_4 1)
+
+# Add the standard library to the build
+target_link_libraries(lab_4
+        pico_stdlib)
+
+# Add the standard include files to the build
+target_include_directories(lab_4 PRIVATE
+  ${CMAKE_CURRENT_LIST_DIR}
+  ${CMAKE_CURRENT_LIST_DIR}/.. # for our common lwipopts or any other standard includes, if required
+)
+
+# Add any user requested libraries
+target_link_libraries(lab_4
+        hardware_pwm
+        hardware_adc
+        )
+
+pico_add_extra_outputs(lab_4)
+
diff --git a/lab_4/lab_4.c b/lab_4/lab_4.c
new file mode 100644
index 0000000..52f3f30
--- /dev/null
+++ b/lab_4/lab_4.c
@@ -0,0 +1,72 @@
+
+/**
+ * To configure a PWM signal at 20 Hz with a 50% duty cycle
+ * on GP2 and feed it into an ADC at GP26 while
+ * sampling the ADC every 25 ms,
+ * you must use the Raspberry Pi Pico and its Pico C SDK.
+ *
+ * You will need to use a jumper wire to connect GP2 to GP26.
+ * You may use a timer interrupt.
+ */
+
+#include <stdio.h>
+#include "pico/stdlib.h"
+#include "hardware/pwm.h"
+#include "hardware/adc.h"
+
+#define PWM_PIN 2
+#define PWM_FREQ 20
+#define PWM_DUTY 0.5
+
+#define ADC_PIN 26
+#define ADC_FREQ 25
+
+void setup () {
+    gpio_set_function(PWM_PIN, GPIO_FUNC_PWM);
+    uint slice_num = pwm_gpio_to_slice_num(PWM_PIN);
+
+    pwm_set_wrap(slice_num, 100);
+    // Setup PWM with 20 Hz frequency and 50% duty cycle
+    pwm_set_chan_level(slice_num, PWM_CHAN_A, PWM_DUTY * 100);
+    pwm_set_enabled(slice_num, true);
+    pwm_set_clkdiv(slice_num, 1);
+
+    // Set up ADC
+    adc_init();
+    adc_gpio_init(ADC_PIN);
+    adc_select_input(0);
+}
+
+bool repeating_timer_callback (struct repeating_timer *t) {
+    // Read ADC value
+    uint16_t result = adc_read();
+    uint64_t time = time_us_64();
+    printf("%02d:%02d:%02d:%03d -> ADC value: %d\n",
+           (int) (time / 3600000000),
+           (int) (time / 60000000) % 60,
+           (int) (time / 1000000) % 60,
+           (int) (time / 1000) % 1000,
+           result
+    );
+
+    return true;
+}
+
+int main () {
+    stdio_init_all();
+    setup();
+
+    struct repeating_timer timer;
+
+    // Setup timer interrupt
+    add_repeating_timer_ms(ADC_FREQ,
+                           repeating_timer_callback,
+                           NULL,
+                           &timer
+    );
+
+    while (true)
+    {
+        tight_loop_contents();
+    }
+}