㈠ android 串口通信丟失數據原因
我現在測試也遇到這個問題,我是根據android_serialport_api裡面的代碼做的,就是在android端接收串口發過來的數據不完整,幾乎每次都只是接收一部分的數據,另外一部分就不知道跑到哪裡去,請問你這個問題你解決了嗎
㈡ 怎麼編譯 串口android-serialport-api
說的幾個問題
要了解在VC6.0必須使用XP系統,win7的安全性是太高了,部分的動態鏈接庫的變化,導致一些程序無法運行。
在WinXP中可以看到,到底出了什麼錯。例如,winxp的報警,請問您的地址讀取錯誤導致程序崩潰,緩沖區溢出,緩沖區溢出,WIN7不喜歡你的頭發,這個數字顯然知道,什麼都不知道的報警
?
其次,在編譯時沒有任何錯誤,但這個語法沒有任何錯誤,但並不意味著該程序是沒有錯誤
例如
詮釋*;
* I = 123;
上述兩者之間沒有任何語法錯誤,但是一運行就死機,表明該內存不能寫入
錯誤的原因很明顯,沒有給一個指針,我被分配一個值的地址,想給一個模糊的地址寫入到123,當然,一個錯誤
沒有問題
詮釋一;
詮釋* I = &A;
* I = 123 / / 123被寫入到介質。
串列通信無非是讀取和寫入文件的讀取與寫入功能
錯誤的原因是讀或寫功能
第二個參數是一個void指針?
或者第一個參數的串口文件指針不存在
或第三個參數是大於與所述第二參數的大小?
㈢ 如何查看Android SDK API文檔
查看android api有兩種方式:在線查看與離線查看。
1. 在線查看
在線查看一般是指在安卓開發者官網上直接查看,但這需要你的網路環境可以訪問谷歌。
官方地址如下:
https://developer.android.com/reference/packages.html
目前最新的API是android 24,如下圖,左邊可以切換API的版本,右邊可以切換顯示包索引還是類索引。
依次打開Develop-->Reference,然後就可以看到API文檔了。這個docs幾乎包含了開發者官網的全部內容,所以除了查看API,還可以查看官方教程等資源。
另外,雖說這是離線文檔,但裡麵包含了谷歌字體服務和幾個連接谷歌的腳本,所以打開時可能會很慢。解決方案是用一個編輯器比如Notepad++,搜索各文件中包含的訪問谷歌服務的網址字串,並將其替換為空串就可以了。
㈣ 如何獲取Android唯一標識
可以用這個,優點不需要任何許可權
// 獲得獨一無二的Psuedo ID
public static String getUniquePsuedoID() {
String serial = null;
String m_szDevIDShort = "35" + Build.BOARD.length() % 10 + Build.BRAND.length() % 10 +
Build.CPU_ABI.length() % 10 + Build.DEVICE.length() % 10 +
Build.DISPLAY.length() % 10 + Build.HOST.length() % 10 +
Build.ID.length() % 10 + Build.MANUFACTURER.length() % 10 +
Build.MODEL.length() % 10 + Build.PRODUCT.length() % 10 +
Build.TAGS.length() % 10 + Build.TYPE.length() % 10 +
Build.USER.length() % 10; // 13 位
try {
serial = android.os.Build.class.getField("SERIAL").get(null).toString();
// API>=9 使用serial號
return new UUID(m_szDevIDShort.hashCode(), serial.hashCode()).toString();
} catch (Exception exception) {
// serial需要一個初始化
serial = "serial"; // 隨便一個初始化
}
// 使用硬體信息拼湊出來的15位號碼
return new UUID(m_szDevIDShort.hashCode(), serial.hashCode()).toString();
}
㈤ 如何在android程序中使用百度api介面
網路地圖、網路語音、網路導航、網路定位等等。
以下為使用網路天氣提供的api,具有天氣查詢,城市設置,簡訊分享天氣等基本功能,界面清爽,不過現在因為網路key的原因失效了,不能更新天氣了。.java中的AK替換成自己申請的網路API KEY,申請地址http://lbsyun..com/apiconsole/key。代碼有比較詳細的注釋。代碼量也不大,有興趣的朋友可以自己排查一下。項目編碼UTF-8 默認編譯版本4.2.2
Android應用源碼使用網路天氣的愛天氣項目源碼 Android應用源碼使用網路天氣的愛天氣項目源碼 Android應用源碼使用網路天氣的愛天氣項目源碼
文件夾 PATH 列表
卷序列號為 767E7528 000A:8F50
E:.
│ 070705 (1).png
│ 070705 (2).png
│ 070705 (3).png
│ javaapk.com文件列表生成工具.bat
│ 更多源碼打包下載.url
│ 本源碼使用幫助.txt
│ 目錄列表.txt
│
└─iWeather
│ .classpath
│ .project
│ AndroidManifest.xml
│ ic_launcher-web.png
│ proguard-project.txt
│ project.properties
│
├─.settings
│ org.eclipse.core.resources.prefs
│ org.eclipse.jdt.core.prefs
│
├─assets
│ └─fonts
│ fangzhenglantingxianhe_GBK.ttf
│ HelveticaNeueLTPro-Lt.ttf
│
│
├─gen
│ └─e
│ └─swust
│ └─iweather
│ BuildConfig.java
│ R.java
│
├─libs
│ │ locSDK_4.0.jar
│ │ wae-for-debug.jar
│ │
│ └─armeabi
│ liblocSDK4.so
│
├─res
│ ├─drawable
│ │ city_pressed_effect.xml
│ │ title_bar_image_pressed_effect.xml
│ │
│ ├─drawable-hdpi
│ │ bg_cloudy_day.jpg
│ │ bg_cloudy_night.jpg
│ │ bg_fine_day.jpg
│ │ bg_fine_night.jpg
│ │ bg_fog.jpg
│ │ bg_haze.jpg
│ │ bg_na.jpg
│ │ bg_overcast.jpg
│ │ bg_rain.jpg
│ │ bg_sand_storm.jpg
│ │ bg_snow.jpg
│ │ bg_thunder_storm.jpg
│ │ city_bg_pressed.9.png
│ │ drag_view_handle.png
│ │ icon.png
│ │ icon_search.png
│ │ ic_launcher.png
│ │ locate_indicator.png
│ │ search_input_bg.9.png
│ │ select_city_bg_cover.9.png
│ │ select_city_bg_default.jpg
│ │ temperature_small_img.png
│ │ title_bar_about.png
│ │ title_bar_back.png
│ │ title_bar_bg.9.png
│ │ title_bar_refresh.png
│ │ title_bar_shared.png
│ │ today_weather_extra_arrow.png
│ │ trend_bg_line.png
│ │ weather_forcast_bg.9.png
│ │ weather_forecast_icon.png
│ │ weather_icon_cloudy.png
│ │ weather_icon_fine.png
│ │ weather_icon_fog.png
│ │ weather_icon_hail.png
│ │ weather_icon_overcast.png
│ │ weather_icon_rain_big.png
│ │ weather_icon_rain_middle.png
│ │ weather_icon_rain_small.png
│ │ weather_icon_rain_snow.png
│ │ weather_icon_rain_storm.png
│ │ weather_icon_sand_storm.png
│ │ weather_icon_sleet.png
│ │ weather_icon_snow_big.png
│ │ weather_icon_snow_middle.png
│ │ weather_icon_snow_small.png
│ │ weather_icon_snow_storm.png
│ │ weather_icon_thunder_storm.png
│ │ weather_img_cloudy_day.png
│ │ weather_img_cloudy_night.png
│ │ weather_img_fine_day.png
│ │ weather_img_fine_night.png
│ │ weather_img_fog.png
│ │ weather_img_hail.png
│ │ weather_img_overcast.png
│ │ weather_img_rain_big.png
│ │ weather_img_rain_middle.png
│ │ weather_img_rain_small.png
│ │ weather_img_rain_snow.png
│ │ weather_img_rain_storm.png
│ │ weather_img_sand_storm.png
│ │ weather_img_sleet.png
│ │ weather_img_snow_big.png
│ │ weather_img_snow_middle.png
│ │ weather_img_snow_small.png
│ │ weather_img_snow_storm.png
│ │ weather_img_thunder_storm.png
│ │ welcome_bg.jpg
│ │ welcome_icon.png
│ │ wind_samll_img.png
│ │
│ ├─drawable-ldpi
│ │ icon.png
│ │
│ ├─drawable-mdpi
│ │ icon.png
│ │ ic_launcher.png
│ │
│ ├─drawable-xhdpi
│ │ icon.png
│ │ ic_launcher.png
│ │
│ ├─drawable-xxhdpi
│ │ icon.png
│ │
│ ├─layout
│ │ city_item.xml
│ │ select_city.xml
│ │ weather.xml
│ │ weather_dialog.xml
│ │ weather_forecast_item.xml
│ │ welcome.xml
│ │
│ └─values
│ colors.xml
│ dimens.xml
│ strings.xml
│ styles.xml
│
└─src
└─e
└─swust
└─iweather
│ SelectCity.java
│ Weather.java
│ Welcome.java
│
├─util
│ Utils.java
│
└─web
SinaWeather.java
UpdateWeather.java
㈥ android串口通信如何發送16進制給給下位機
已解決,發送串口幀數據時,對於16進制數據定義,直接用byte[]數組就行了,不需要用Array.fill函數;
㈦ 誰有沒有Android串口的使用例子
1 首先做的是創建新的工程然後添加一下文件
3代碼
好了 然後就是關於這個頁面的Code了,
這是我的:
package android.serialport;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.text.BreakIterator;
import java.util.ServiceConfigurationError;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class MyserialActivity extendsActivity
{
EditText sendedit;
EditText receiveedit;
FileInputStream mInStream;
FileOutputStream mOutStream;
SerialPort classserialport;
ReadThread mReadThread;
private class ReadThread extends Thread
{
public void run()
{
super.run();
while(!isInterrupted())
{
int size;
}
}
}
void onDataReceive(final byte[] buffer,finalint size)
{
runOnUiThread(new Runnable()
{
@Override
publicvoid run()
{
// TODO Auto-generated method stub
if(mReadThread != null)
{
receiveedit.append(newString(buffer,0,size));
}
}
});
}
@Override
protectedvoid onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
this.requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.activity_myserial);
sendedit= (EditText)findViewById(R.id.editText1);
receiveedit=(EditText)findViewById(R.id.editText2);
receiveedit.setFocusable(false);//進制輸入
/*
* 打開串口
* */
finalButton openserial =(Button)findViewById(R.id.button1);
openserial.setOnClickListener(newView.OnClickListener()
{
@Override
publicvoid onClick(View arg0)
{
//TODO Auto-generated method stub
try
{
classserialport=new SerialPort(new File("/dev/ttyS2"),9600);
}catch(SecurityExceptione)
{
e.printStackTrace();
}
catch(IOExceptione)
{
e.printStackTrace();
}
mInStream=(FileInputStream) classserialport.getInputStream();
Toast.makeText(MyserialActivity.this,"串口打開成功",Toast.LENGTH_SHORT).show();
}
});
/*
* 發送數據
* */
finalButton sendButton =(Button)findViewById(R.id.button2);
sendButton.setOnClickListener(newView.OnClickListener()
{
@Override
publicvoid onClick(View arg0)
{
Stringindata;
indata=sendedit.getText().toString();
//TODO Auto-generated method stub
try
{
mOutStream=(FileOutputStream) classserialport.getOutputStream();
mOutStream.write(indata.getBytes());
mOutStream.write('
');
}
catch(IOExceptione)
{
e.printStackTrace();
}
Toast.makeText(MyserialActivity.this,"數據發送成功",Toast.LENGTH_SHORT).show();
sendedit.setText("");
}
});
/*
* 接收數據
* */
finalButton receButton= (Button)findViewById(R.id.button3);
receButton.setOnClickListener(newView.OnClickListener()
{//inttag =0;
@Override
publicvoid onClick(View arg0)
{
// TODO Auto-generated method stub
intsize;
try
{
byte[]buffer = new byte[64];
if(mInStream== null) return;
size= mInStream.read(buffer);
if(size>0)
{
receiveedit.setText("");
}
if(size>0)
{
onDataReceive(buffer,size);
}
inttag =1;
receiveedit.setText(newString(buffer, 0, size));
}catch(IOExceptione)
{
e.printStackTrace();
return;
}
}
privateboolean isInterrupted()
{
// TODO Auto-generated methodstub
returnfalse;
}
});
/*
* 清楚接收區
* */
finalButton ClearButton = (Button)findViewById(R.id.clear);
ClearButton.setOnClickListener(newView.OnClickListener()
{
@Override
publicvoid onClick(View arg0)
{
//TODO Auto-generated method stub
receiveedit.setText("");
}
});}
@Override
publicboolean onCreateOptionsMenu(Menu menu)
{
//Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.myserial,menu);
returntrue;
}
}
好吧 你做好了。
3需要載入的文件
下面我把所需要添加的代碼貼一貼
第一個是Serialport.java
/*
* Copyright 2009 Cedric Priscal
*
* 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 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.
*/
package android.serialport;
import java.io.File;
import java.io.FileDescriptor;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import android.util.Log;
public class SerialPort {
private static final String TAG = "SerialPort";
/*
* Do not remove or rename the field mFd: it is used by native method close();
*/
private FileDescriptor mFd; //創建一個文件描述符對象 mFd
private FileInputStream mFileInputStream;
private FileOutputStream mFileOutputStream;
public SerialPort(File device, int baudrate) throws SecurityException, IOException {
/*
* 檢查訪問許可權
* */
/* Check access permission */
if (!device.canRead() || !device.canWrite()) {//如果設備不可讀或者設備不可寫
try {
/* Missing read/write permission, trying to chmod the file *///沒有讀寫許可權,就嘗試去掛載許可權
Process su; //流程進程 su
su = Runtime.getRuntime().exec("/system/bin/su");//通過執行掛載到/system/bin/su 獲得執行
String cmd = "chmod 777 " + device.getAbsolutePath() + "
"
+ "exit
";
/*String cmd = "chmod 777 /dev/s3c_serial0" + "
"
+ "exit
";*/
su.getOutputStream().write(cmd.getBytes());//進程。獲得輸出流。寫(命令。獲得二進制)
if ((su.waitFor() != 0) || !device.canRead()
|| !device.canWrite()) {//如果 進程等待不是0 或者 設備不能讀寫就
throw new SecurityException();//拋出一個許可權異常
}
} catch (Exception e) {
e.printStackTrace();
throw new SecurityException();
}
}
/*
*
* */
mFd = open(device.getAbsolutePath(), baudrate);
//device.getAbsolutePath()這是要掛載的路徑new File("/dev/ttyS2")
if (mFd == null) {
Log.e(TAG, "native open returns null");
throw new IOException();//輸入輸出異常
}
//將文件描述符 做輸入輸出流的參數 傳遞給創建的輸入輸出流
mFileInputStream = new FileInputStream(mFd);
mFileOutputStream = new FileOutputStream(mFd);
}
// Getters and setters
public InputStream getInputStream() {
return mFileInputStream;
}
public OutputStream getOutputStream() {
return mFileOutputStream;
}
// JNI
private native static FileDescriptor open(String path, int baudrate);
public native void close();
static {
System.loadLibrary("serial_port");
}
}
第二個是SerialPortFinder.java
/*
* Copyright 2009 Cedric Priscal
*
* 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 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.
*/
package android.serialport;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.io.LineNumberReader;
import java.util.Iterator;
import java.util.Vector;
import android.util.Log;
public class SerialPortFinder {
/*
* 創建一個驅動程序類
* */
public class Driver {
public Driver(String name, String root) {
mDriverName = name;//String 類型的
mDeviceRoot = root;
}
private String mDriverName;
private String mDeviceRoot;
Vector<File> mDevices = null;
/*
* Vector 類在 java 中可以實現自動增長的對象數組
* 簡單的使用方法如下:
vector<int> test;//建立一個vector
test.push_back(1);
test.push_back(2);//把1和2壓入vector這樣test[0]就是1,test[1]就是2
* */
public Vector<File> getDevices() {
if (mDevices == null) {
mDevices = new Vector<File>();
File dev = new File("/dev");
File[] files = dev.listFiles();
int i;
for (i=0; i<files.length; i++) {
if (files[i].getAbsolutePath().startsWith(mDeviceRoot)) {
Log.d(TAG, "Found new device: " + files[i]);
mDevices.add(files[i]);
}
}
}
return mDevices;
}
public String getName() {
return mDriverName;
}
}
/*
*
*
* */
private static final String TAG = "SerialPort";
private Vector<Driver> mDrivers = null;
Vector<Driver> getDrivers() throws IOException {
if (mDrivers == null) {
mDrivers = new Vector<Driver>();
LineNumberReader r = new LineNumberReader(new FileReader("/proc/tty/drivers"));
String l;
while((l = r.readLine()) != null) {
String[] w = l.split(" +");
if ((w.length == 5) && (w[4].equals("serial"))) {
Log.d(TAG, "Found new driver: " + w[1]);
mDrivers.add(new Driver(w[0], w[1]));
}
}
r.close();
}
return mDrivers;
}
public String[] getAllDevices() {
Vector<String> devices = new Vector<String>();
// Parse each driver
Iterator<Driver> itdriv;
try {
itdriv = getDrivers().iterator();
while(itdriv.hasNext()) {
Driver driver = itdriv.next();
Iterator<File> itdev = driver.getDevices().iterator();
while(itdev.hasNext()) {
String device = itdev.next().getName();
String value = String.format("%s (%s)", device, driver.getName());
devices.add(value);
}
}
} catch (IOException e) {
e.printStackTrace();
}
return devices.toArray(new String[devices.size()]);
}
public String[] getAllDevicesPath() {
Vector<String> devices = new Vector<String>();
// Parse each driver
Iterator<Driver> itdriv;
try {
itdriv = getDrivers().iterator();
while(itdriv.hasNext()) {
Driver driver = itdriv.next();
Iterator<File> itdev = driver.getDevices().iterator();
while(itdev.hasNext()) {
String device = itdev.next().getAbsolutePath();
devices.add(device);
}
}
} catch (IOException e) {
e.printStackTrace();
}
return devices.toArray(new String[devices.size()]);
}
}
第三個是Android.mk
#
# Copyright 2009 Cedric Priscal
#
# 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 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.
#
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
TARGET_PLATFORM := android-3
LOCAL_MODULE := serial_port
LOCAL_SRC_FILES := SerialPort.c
LOCAL_LDLIBS := -llog
include $(BUILD_SHARED_LIBRARY)
第四個是SerialPort.c
/*
* Copyright 2009 Cedric Priscal
*
* 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 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 <termios.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>
#include <jni.h>
#include "android/log.h"
static const char *TAG="serial_port";
#define LOGI(fmt, args...) __android_log_print(ANDROID_LOG_INFO, TAG, fmt, ##args)
#define LOGD(fmt, args...) __android_log_print(ANDROID_LOG_DEBUG, TAG, fmt, ##args)
#define LOGE(fmt, args...) __android_log_print(ANDROID_LOG_ERROR, TAG, fmt, ##args)
static speed_t getBaudrate(jint baudrate)
{
switch(baudrate) {
case 0: return B0;
case 50: return B50;
case 75: return B75;
case 110: return B110;
case 134: return B134;
case 150: return B150;
case 200: return B200;
case 300: return B300;
case 600: return B600;
case 1200: return B1200;
case 1800: return B1800;
case 2400: return B2400;
case 4800: return B4800;
case 9600: return B9600;
case 19200: return B19200;
case 38400: return B38400;
case 57600: return B57600;
case 115200: return B115200;
case 230400: return B230400;
case 460800: return B460800;
case 500000: return B500000;
case 576000: return B576000;
case 921600: return B921600;
case 1000000: return B1000000;
case 1152000: return B1152000;
case 1500000: return B1500000;
case 2000000: return B2000000;
case 2500000: return B2500000;
case 3000000: return B3000000;
case 3500000: return B3500000;
case 4000000: return B4000000;
default: return -1;
}
}
/*
* Class: cedric_serial_SerialPort
* Method: open
* Signature: (Ljava/lang/String;)V
*/
JNIEXPORT jobject JNICALL Java_android_serialport_SerialPort_open
(JNIEnv *env, jobject thiz, jstring path, jint baudrate)
{
int fd;
speed_t speed;
jobject mFileDescriptor;
/* Check arguments */
{
speed = getBaudrate(baudrate);
if (speed == -1) {
/* TODO: throw an exception */
LOGE("Invalid baudrate");
return NULL;
}
}
/* Opening device */
{
jboolean is;
const char *path_utf = (*env)->GetStringUTFChars(env, path, &is);
LOGD("Opening serial port %s", path_utf);
fd = open(path_utf, O_RDWR | O_DIRECT | O_SYNC);
LOGD("open() fd = %d", fd);
(*env)->ReleaseStringUTFChars(env, path, path_utf);
if (fd == -1)
{
/* Throw an exception */
LOGE("Cannot open port");
/* TODO: throw an exception */
return NULL;
}
}
/* Configure device */
{
struct termios cfg;
LOGD("Configuring serial port");
if (tcgetattr(fd, &cfg))
{
LOGE("tcgetattr() failed");
close(fd);
/* TODO: throw an exception */
return NULL;
}
cfmakeraw(&cfg);
cfsetispeed(&cfg, speed);
cfsetospeed(&cfg, speed);
if (tcsetattr(fd, TCSANOW, &cfg))
{
LOGE("tcsetattr() failed");
close(fd);
/* TODO: throw an exception */
return NULL;
}
}
/* Create a corresponding file descriptor */
{
jclass cFileDescriptor = (*env)->FindClass(env, "java/io/FileDescriptor");
jmethodID iFileDescriptor = (*env)->GetMethodID(env, cFileDescriptor, "<init>", "()V");
jfieldID descriptorID = (*env)->GetFieldID(env, cFileDescriptor, "descriptor", "I");
mFileDescriptor = (*env)->NewObject(env, cFileDescriptor, iFileDescriptor);
(*env)->SetIntField(env, mFileDescriptor, descriptorID, (jint)fd);
}
return mFileDescriptor;
}
/*
* Class: cedric_serial_SerialPort
* Method: close
* Signature: ()V
*/
JNIEXPORT void JNICALL Java_android_serialport_SerialPort_close
(JNIEnv *env, jobject thiz)
{
jclass SerialPortClass = (*env)->GetObjectClass(env, thiz);
jclass FileDescriptorClass = (*env)->FindClass(env, "java/io/FileDescriptor");
jfieldID mFdID = (*env)->GetFieldID(env, SerialPortClass, "mFd", "Ljava/io/FileDescriptor;");
jfieldID descriptorID = (*env)->GetFieldID(env, FileDescriptorClass, "descriptor", "I");
jobject mFd = (*env)->GetObjectField(env, thiz, mFdID);
jint descriptor = (*env)->GetIntField(env, mFd, descriptorID);
LOGD("close(fd = %d)", descriptor);
close(descriptor);
}
㈧ android串口消息
android串口消息連接的方法為:
1.模擬器可以使用PC的串口。
啟動模擬器並載入PC串口 命令如下。
運行 emulator @模擬器名稱 -qmu -serial COM1。
2.查看串口是否被載入。
啟動後使用 adb shell 命令打開命令行
cd dev 查看會發現ttyS0 ttyS1 ttyS2,其他ttyS2 就是我們載入上來的串口COM1
3.修改許可權
chmod 777 ttyS2
現在我們可以開發串口程序了。
4.串口程序實例
下載libserial_port.so ,放入libs/armeabi 目錄,可以自己創建此目錄
libserial_port.so 下載地址:
http://code.google.com/p/android-serialport-api/
import java.io.File;
import java.io.FileDescriptor;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import android.util.Log;
public class SerialPort {
private static final String TAG = "SerialPort";
private FileDescriptor mFd;
private FileInputStream mFileInputStream;
private FileOutputStream mFileOutputStream;
public SerialPort(File device, int baudrate) throws SecurityException, IOException {
if (!device.canRead() || !device.canWrite()) {
try {
Process su;
su = Runtime.getRuntime().exec("/system/bin/su");
String cmd = "chmod 666 " + device.getAbsolutePath() + "n"
+ "exitn";
su.getOutputStream().write(cmd.getBytes());
if ((su.waitFor() != 0) || !device.canRead()
|| !device.canWrite()) {
throw new SecurityException();
}
} catch (Exception e) {
e.printStackTrace();
throw new SecurityException();
}
}
mFd = open(device.getAbsolutePath(), baudrate);
if (mFd == null) {
Log.e(TAG, "native open returns null");
throw new IOException();
}
mFileInputStream = new FileInputStream(mFd);
mFileOutputStream = new FileOutputStream(mFd);
}
public InputStream getInputStream() {
return mFileInputStream;
}
public OutputStream getOutputStream() {
return mFileOutputStream;
}
//JNI
private native static FileDescriptor open(String path, int baudrate);
public native void close();
static {
System.loadLibrary("serial_port");
}
}
####################################
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
public class PrintClass {
//輸入流
private static InputStream in;
//輸出流
private static OutputStream out;
private static final String PORT = "/dev/ttyS2";//串口
private SerialPort serialPort;
private void Connect()
{
try {
serialPort = new SerialPort(new File(PORT), 38400);
in = serialPort.getInputStream();
out = serialPort.getOutputStream();
} catch (SecurityException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
public void CloseSerialPort()
{
try {
out.close();
in.close();
serialPort.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
㈨ 如何開放android的串口許可權
要調用串口,肯定是要用到JNI的,而且要有打開對應串口設備的許可權
至於是不是通過USB轉的,沒啥關系,因為USB轉串口的驅動已經把USB的特徵封裝了,就當它是一個純串口操作就行
android-serialport-api也是用的JNI,要想知道能不能用,裝它的DEMO代碼試試就知道了
不然重新寫一個JNI的庫,用android-serialport-api的也行,不然網上也好多現成的代碼,基本不用重寫