Initial Release

pwm/hello_pwm/CMakeLists.txt

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+add_executable(hello_pwm
+        hello_pwm.c
+        )
+
+# Pull in our pico_stdlib which pulls in commonly used features
+target_link_libraries(hello_pwm pico_stdlib hardware_pwm)
+
+# create map/bin/hex file etc.
+pico_add_extra_outputs(hello_pwm)
+
+# add url via pico_set_program_url
+example_auto_set_url(hello_pwm)

pwm/hello_pwm/hello_pwm.c

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+/**
+ * Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+// Output PWM signals on pins 0 and 1
+
+#include "pico/stdlib.h"
+#include "hardware/pwm.h"
+
+int main() {
+    ///tag::setup_pwm[]
+
+    // Tell GPIO 0 and 1 they are allocated to the PWM
+    gpio_set_function(0, GPIO_FUNC_PWM);
+    gpio_set_function(1, GPIO_FUNC_PWM);
+
+    // Find out which PWM slice is connected to GPIO 0 (it's slice 0)
+    uint slice_num = pwm_gpio_to_slice_num(0);
+
+    // Set period of 4 cycles (0 to 3 inclusive)
+    pwm_set_wrap(slice_num, 3);
+    // Set channel A output high for one cycle before dropping
+    pwm_set_chan_level(slice_num, PWM_CHAN_A, 1);
+    // Set initial B output high for three cycles before dropping
+    pwm_set_chan_level(slice_num, PWM_CHAN_B, 3);
+    // Set the PWM running
+    pwm_set_enabled(slice_num, true);
+    ///end::setup_pwm[]
+
+    // Note we could also use pwm_set_gpio_level(gpio, x) which looks up the
+    // correct slice and channel for a given GPIO.
+}