模仿carlin MYLED写了一个mytimer(PWM) 蜂鸣器响了 哦哈哈

按照myled先整了一遍led
如上先整了一个jni
然后是在java中调用
但是蜂鸣器毫无反应
我表示很郁闷。。。
mytimer.rar (82 K) 下载次数:42
这是jni

复制代码 /* * Copyright (C) 2009 The Android Open Source Project * * 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 <string.h> #include <jni.h> #include <fcntl.h> /*包括文件操作，如open() read() close()write()等*/ int fd; /* This is a trivial JNI example where we use a native method * to return a new VM String. See the corresponding Java source * file located at: * *   apps/samples/hello-jni/project/src/com/example/HelloJni/HelloJni.java */ jstring Java_com_PwmCtr_PwmCtr_stringFromJNI( JNIEnv* env,                                                   jobject thiz ) {     return (*env)->NewStringUTF(env, "Hello from JNI create by carlin !"); } jint Java_com_PwmCtr_PwmCtr_open( JNIEnv* env,         jobject thiz ) {     fd = open("/dev/pwm", O_RDONLY);     if (fd < 0)     {         fd = open("/dev/pwm", O_RDONLY);         return 1;     }     return 0; } jint Java_com_PwmCtr_PwmCtr_ioctrl( JNIEnv* env,         jobject thiz ,jint cmd,jlong arg) {     ioctl(fd,cmd, arg);     return 1; } jint Java_com_PwmCtr_PwmCtr_close( JNIEnv* env,         jobject thiz ) {     close(fd);     return 1; }

这是pwmctrl类

复制代码 package com.PwmCtr; public class PwmCtr {     public native int open();     public native int ioctrl(int cmd ,long  arg);     public native int close();     public native String  unimplementedStringFromJNI();     static {         System.loadLibrary("pwm-jni");     } }

这是activity

复制代码 package com.Mytimer; import android.app.Activity; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import com.Mytimer.R; import com.PwmCtr.PwmCtr; public class MytimerActivity extends Activity implements OnClickListener{        private Button Bt1;     private Button Bt2;     private Button Bt3;     private static long frq=0;     PwmCtr pwm;          /** Called when the activity is first created. */     @Override     public void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.main);         frq=0;         pwm=new PwmCtr();         pwm.open();         pwm.ioctrl(0,0);                  Bt1 = (Button)findViewById(R.id.button1);         Bt2 = (Button)findViewById(R.id.button2);         Bt3 = (Button)findViewById(R.id.button3);                  Bt1.setOnClickListener(this);         Bt2.setOnClickListener(this);         Bt3.setOnClickListener(this);     }              public void onClick(View v) {                  switch (v.getId()) {         case R.id.button1:             frq+=1000;             pwm.ioctrl(1,frq);//关闭蜂鸣器             break;         case R.id.button2:             if(frq>1000)             {                 frq-=1000;             }             else             {                 frq=0;             }             pwm.ioctrl(1,frq);//关闭蜂鸣器             break;         case R.id.button3:             pwm.ioctrl(0,0);//关闭蜂鸣器                          break;             default:                 break;         }    } }

应用程序没有挂吧， 蜂鸣器是不是好的

是参数名称不匹配
java中的参数名称类型一定要与jni.c中的参数名称 类型一致
否则调用不成功