#2020征文-开发板#红绿黄灯板的使用

wifiiot套件的板子很多，今天先来写一篇关于使用红绿灯板的帖子。主要完成红绿灯板，LED、蜂鸣器、按键的控制。

# 一、硬件介绍

通过查看红绿灯板的原理图，红绿灯板主要有红、绿、黄LED灯各一个，蜂鸣器一个，按键一个。

经过查看原理图，它们使用主控的GPIO口分别为：
red         --》 GPIO10
green     --》 GPIO11
yellow    --》 GPIO12
beep       --》GPIO9

switch     --》GPIO8

# 二、新建文件

之前一直做的都是MCU这方面的开发，习惯了使用IDE,对一些编译工具链都没什么了解。对于怎么在原来的工程目录下，新建文件不是很熟悉。但是这些都不是什么大问题，可以看原来的工程目录结构是怎么样的，按照它的模板进行新建就行了。
好像就是一个文件夹下存放.c .h文件和BUILD.gn。

 好的，我们就那样来开干。在app目录下新建SSL文件夹，下面再新建c文件和BUILD.gn文件。

## 1、light.c

该C文件任务主要是控制红绿黄灯亮灭。把原来的led例程复制过来进行更改。
新建一个任务，红绿灯一秒亮，一秒灭循环闪烁。

    /*
    * Copyright (c) 2020 Huawei Device Co., Ltd.
    * 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 <stdio.h>

    #include <unistd.h>

    #include "ohos_init.h"
    #include "cmsis_os2.h"
    #include "wifiiot_gpio.h"
    #include "wifiiot_gpio_ex.h"

    #define LIGHT_INTERVAL_TIME_US 1000000
    #define LIGHT_TASK_STACK_SIZE 512
    #define LIGHT_TASK_PRIO 26

    #define YELLOW_GPIO  WIFI_IOT_IO_NAME_GPIO_12
    #define GREEN_GPIO   WIFI_IOT_IO_NAME_GPIO_11
    #define RED_GPIO     WIFI_IOT_IO_NAME_GPIO_10



    static void *LightTask(const char *arg)
    {
        (void)arg;
        while (1) {
                    GpioSetOutputVal(YELLOW_GPIO, 1);
                    GpioSetOutputVal(RED_GPIO,1);
                    GpioSetOutputVal(GREEN_GPIO,1);
                    usleep(LIGHT_INTERVAL_TIME_US);
                    GpioSetOutputVal(YELLOW_GPIO, 0);
                    GpioSetOutputVal(RED_GPIO,0);
                    GpioSetOutputVal(GREEN_GPIO,0);
                    usleep(LIGHT_INTERVAL_TIME_US);
            }

        return NULL;
    }

    static void LightTaskEntry(void)
    {
        osThreadAttr_t attr;

        GpioInit();
        IoSetFunc(WIFI_IOT_IO_NAME_GPIO_10, WIFI_IOT_IO_FUNC_GPIO_10_GPIO);
        GpioSetDir(WIFI_IOT_IO_NAME_GPIO_10, WIFI_IOT_GPIO_DIR_OUT);
       
        IoSetFunc(WIFI_IOT_IO_NAME_GPIO_11, WIFI_IOT_IO_FUNC_GPIO_11_GPIO);
        GpioSetDir(WIFI_IOT_IO_NAME_GPIO_11, WIFI_IOT_GPIO_DIR_OUT);
       
        IoSetFunc(WIFI_IOT_IO_NAME_GPIO_12, WIFI_IOT_IO_FUNC_GPIO_12_GPIO);
        GpioSetDir(WIFI_IOT_IO_NAME_GPIO_12, WIFI_IOT_GPIO_DIR_OUT);

        attr.name = "LightTask";
        attr.attr_bits = 0U;
        attr.cb_mem = NULL;
        attr.cb_size = 0U;
        attr.stack_mem = NULL;
        attr.stack_size = LIGHT_TASK_STACK_SIZE;
        attr.priority = LIGHT_TASK_PRIO;

        if (osThreadNew((osThreadFunc_t)LightTask, NULL, &attr) == NULL) {
            printf("[LightTask] Falied to create LightTask!\n");
        }
    }

    SYS_RUN(LightTaskEntry);

2、beep.c

该C文件任务主要任务是通过按下按键，控制蜂鸣器发声。
新建任务，按下按键，蜂鸣器发声，松开按键，蜂鸣器停止发声。
这里要注意一下，按键的引脚信号为输入信号，初始化的时候，需要先进行上拉模式设置，要不然会一直检测到低电平。

    /*
    * Copyright (c) 2020 Huawei Device Co., Ltd.
    * 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 <stdio.h>

    #include <unistd.h>

    #include "ohos_init.h"
    #include "cmsis_os2.h"
    #include "wifiiot_gpio.h"
    #include "wifiiot_gpio_ex.h"

    #define BEEP_INTERVAL_TIME_US 1000000
    #define BEEP_TASK_STACK_SIZE 512
    #define BEEP_TASK_PRIO 27

    #define BEEP_GPIO  WIFI_IOT_IO_NAME_GPIO_9
    #define BUTTON_GPIO   WIFI_IOT_IO_NAME_GPIO_8

    #define BUTTON_CHECK_DELAY_US   5000


    static void *BeepTask(const char *arg)
    {
        (void)arg;
        while (1) {

                WifiIotGpioValue buttonValue;
                GpioGetInputVal(BUTTON_GPIO ,&buttonValue);
                if(buttonValue == WIFI_IOT_GPIO_VALUE0){
                    GpioSetOutputVal(BEEP_GPIO, 1);
                    usleep(BUTTON_CHECK_DELAY_US);
                    GpioSetOutputVal(BEEP_GPIO, 0);
                    usleep(BUTTON_CHECK_DELAY_US);
                }
                usleep(BUTTON_CHECK_DELAY_US);

            }

        return NULL;
    }


    static void BeepTaskEntry(void)
    {

        osThreadAttr_t attr;

        GpioInit();
        IoSetFunc(WIFI_IOT_IO_NAME_GPIO_8, WIFI_IOT_IO_FUNC_GPIO_8_GPIO);
        GpioSetDir(WIFI_IOT_IO_NAME_GPIO_8, WIFI_IOT_GPIO_DIR_IN);
        IoSetPull(WIFI_IOT_IO_NAME_GPIO_8,WIFI_IOT_IO_PULL_UP);

        IoSetFunc(WIFI_IOT_IO_NAME_GPIO_9, WIFI_IOT_IO_FUNC_GPIO_9_GPIO);
        GpioSetDir(WIFI_IOT_IO_NAME_GPIO_9, WIFI_IOT_GPIO_DIR_OUT);

        attr.name = "BeepTask";
        attr.attr_bits = 0U;
        attr.cb_mem = NULL;
        attr.cb_size = 0U;
        attr.stack_mem = NULL;
        attr.stack_size = BEEP_TASK_STACK_SIZE;
        attr.priority = BEEP_TASK_PRIO;

        if (osThreadNew((osThreadFunc_t)BeepTask, NULL, &attr) == NULL) {
            printf("[BeepTask] Falied to create BeepTask!\n");
        }
    }

    SYS_RUN(BeepTaskEntry);

3、BUILD.gn

对于我这种只习惯于IDE开发，对这类文件都不熟悉，但是这些都些东西都是有规律的，看其他的文件夹下的BUILD.gn是怎么编写的，然后复制更改。

# Copyright (c) 2020 Huawei Device Co., Ltd.
# 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.

static_library("ssl_example") {
    sources = [
        "light.c",
        "beep.c"
    ]

    include_dirs = [
        "//utils/native/lite/include",
        "//kernel/liteos_m/components/cmsis/2.0",
        "//base/iot_hardware/inteRFaces/kits/wifiiot_lite",
    ]
}

 这样还不行，还要修改app文件夹下的BUILD.gn。

    # Copyright (c) 2020 Huawei Device Co., Ltd.
    # 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.

    import("//build/lite/config/component/lite_component.gni")

    lite_component("app") {
        features = [
            "startup",
            "SSL:ssl_example",
        ]
    }

 三、编译下载

 下载验证成功。