android串口驅動

1. 怎麼查看android 設備的串口

1. 如果是linux，不需要單獨安裝什麼串口驅動
2. 但需要使用ls /dev/tty * 查看usb 串口設備是否被檢測到
2. 然後使用linux下的MINICOM進行串口信息列印，具體配置和用法可以一下

2. Android8.1系統修改串口節點

        應客戶需求，需要將Android系統裡面的串口4（/dev/ttyS4）節點名稱修改為/dev/ttyS9。

        由於設備節點都是在驅動裡面注冊生成的於是查看串口驅動。根據log信息找到了系統串口驅動\kernel\drivers\tty\serial\8250\8250_dw.c中的注冊函數dw8250_probe。該函數中找到serial8250_register_8250_port，這個是注冊設備節點的函數。然後查看serial8250_register_8250_port函數定義（kernel\drivers\tty\serial\老山租8250\8250_core.c），找到了後續注冊節點的函數uart_add_one_port，繼續查看該函數（位於kernel\drivers\tty\serial\serial_core.c）定義，該函數又是調用tty_port_register_device_attr進行注冊的，繼續跟蹤該函數（侍兆kernel\drivers\tty\tty_port.c），該函數又是調用了tty_register_device_attr（位於kernel\drivers\tty\tty_io.c）進行注冊。添加log分析得知串口節點唯虛的名字獲取是由tty_line_name產生的。於是查看tty_line_name的實現：

static ssize_t tty_line_name(struct tty_driver *driver, int index, char *p)

{

if (driver->flags & TTY_DRIVER_UNNUMBERED_NODE)

return sprintf(p, "%s", driver->name);

else

return sprintf(p, "%s%d", driver->name,

  index + driver->name_base);

}

}

通過列印得知串口節點設備名稱是由驅動名稱 driver->name和串口序號index 組成的，於是添加判斷 driver->name是否為"ttyS",index是否為4，如果是就替換。

3. 如何遠程登錄android開發板

1、安裝adb驅動（adb驅動最好是最新的，要支持adb connect ip命令，可以用cmd中輸入adb查看是否支持）

2、確保開發板能上網，如果不行，在開發板的串口終端中輸入：netcfg eth0 dhcp然後查看ip用ifconfig3、在cmd中ping 開發板ip地址，能ping通就ok了4、在cmd中輸入adb connect ip如：adb connect 192.168.0.146

如果顯示連接成功，則可繼續執行後面的操作；如果不成功，如顯示：unable to connect to 192.168.0.146:5555

有可能是設備監聽埠的問題，則可以在手機終端執行如下命令：setprop service.adb.tcp.port 5555 //設置監聽的埠，埠可以自定義，如5554，5555是默認的stop adbd //關閉adbdstart adbd //重新啟動adbd5、在cmd中輸入adb kill-server，然後重復第四步即可！

4. 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

5. 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();
}
}

}

6. 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);
}