pwm.cc

// Copyright 2022 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include "libs/base/pwm.h"

#include "libs/base/led.h"
#include "third_party/freertos_kernel/include/FreeRTOS.h"
#include "third_party/freertos_kernel/include/task.h"

// Runs simple PWM cycles with pins PWM_A (pin 10 on the left-side header)
// and PWM_B (pin 9 on the left-side header).
// Note: These pins output a max of 1.8V
//
// To build and flash from coralmicro root:
//    bash build.sh
//    python3 scripts/flashtool.py -e pwm

namespace coralmicro {
namespace {
// [start-sphinx-snippet:pwm]
[[noreturn]] void Main() {
  printf("PWM Example!\r\n");
  // Turn on Status LED to show the board is on.
  LedSet(Led::kStatus, true);

  PwmInit();
  PwmPinConfig pin_a_config{.duty_cycle = 20,
                            .frequency = 1000,
                            .pin_setting = PwmPinSettingFor(PwmPin::k10)};
  PwmPinConfig pin_b_config{.duty_cycle = 80,
                            .frequency = 1000,
                            .pin_setting = PwmPinSettingFor(PwmPin::k9)};
  std::vector<PwmPinConfig> configs = {pin_a_config, pin_b_config};
  while (true) {
    PwmEnable(configs);
    vTaskDelay(pdMS_TO_TICKS(1000));
    PwmDisable(configs);
    vTaskDelay(pdMS_TO_TICKS(1000));
  }
}
// [end-sphinx-snippet:pwm]
}  // namespace
}  // namespace coralmicro

extern "C" [[noreturn]] void app_main(void* param) {
  (void)param;
  coralmicro::Main();
}