android Usb串口通信

package com.um.conn; import com.ftdi.j2xx.D2xxManager; import com.ftdi.j2xx.FT_Device; import android.util.Log; public class UsbSerialConnection { private static final int MAX_READBUF_SIZE = 256; private static final int USB_READ_BUFFER_SIZE = 256; private long delay = 1000; private static final int USB_WRITE_BUFFER_SIZE = 256; private long interval = 0; private long start = 0; private long timeout = 2000; private FT_Device ftDevice; private boolean stopFlag = false; private ReadLisener lisener = null; public UsbSerialConnection(FT_Device device) { this.ftDevice = device; this.setConfig(new UsbSerialConnParameter()); } public void setConfig(UsbSerialConnParameter parameter) { if (!ftDevice.isOpen()) { Log.e("j2xx", "SetConfig: device not open"); return; } // configure our port // reset to UART mode for 232 devices ftDevice.setBitMode((byte) 0, D2xxManager.FT_BITMODE_RESET); ftDevice.setBaudRate(parameter.getBaudRate()); ftDevice.setDataCharacteristics(parameter.getDataBits(), parameter.getStopBits(), parameter.getParity()); ftDevice.setLatencyTimer((byte) 16); ftDevice.purge((byte) (D2xxManager.FT_PURGE_TX)); } public void setConfig(UsbSerialConnParameter parameter, long delay) { this.setConfig(parameter); this.delay = delay; } public int write(byte[] buf, int size) { if (buf == null) { return 0; } int offset = 0; int write_size; int written_size; byte[] wbuf = new byte[USB_WRITE_BUFFER_SIZE]; while (offset < size) { write_size = USB_WRITE_BUFFER_SIZE; if (offset + write_size > size) { write_size = size - offset; } System.arraycopy(buf, offset, wbuf, 0, write_size); synchronized (ftDevice) { written_size = ftDevice.write(wbuf, write_size); } if (written_size < 0) { return -1; } offset += written_size; } return offset; } public void close() { this.closeReadThread(); this.restInterval(); this.enableRead(false); } public void closeDevice() { this.closeReadThread(); this.restInterval(); // this.enableRead(false); if (ftDevice.setBreakOff()) { this.ftDevice.close(); this.ftDevice = null; } } private class readThread extends Thread { readThread() { this.setPriority(Thread.MIN_PRIORITY); } @Override public void run() { int len = 0; byte[] rbuf = new byte[USB_READ_BUFFER_SIZE]; while (stopFlag) { try { Thread.sleep(500); } catch (InterruptedException e) { } synchronized (ftDevice) { len = ftDevice.getQueueStatus(); if (len > 0) { if (len > MAX_READBUF_SIZE) { len = MAX_READBUF_SIZE; } ftDevice.read(rbuf, len, delay); if (lisener != null) { if (start == 0) { start = System.currentTimeMillis(); } lisener.onRead(rbuf, len); interval = System.currentTimeMillis() - start; } } else { // 读取超时，即通信无响应 if (lisener != null) { if (start == 0) { start = System.currentTimeMillis(); } if (System.currentTimeMillis() - start > timeout) { lisener.onReadTimeOut(); close(); } } } } if (!stopFlag) { break; } } } } public void enableRead(boolean enableReadFlag) { if (enableReadFlag) { ftDevice.purge((byte) (D2xxManager.FT_PURGE_RX | D2xxManager.FT_PURGE_TX)); ftDevice.restartInTask(); } else { if (ftDevice != null && !ftDevice.stoppedInTask()) { ftDevice.stopInTask(); } } } public void setLisener(ReadLisener lisener) { this.lisener = lisener; } public void startReadThread() { stopFlag = true; this.restInterval(); this.enableRead(true); new readThread().start(); } public void closeReadThread() { stopFlag = false; } public long getDelay() { return delay; } public void setDelay(long delay) { this.delay = delay; } public long getInterval() { return interval; } public void restInterval() { this.start = 0; this.interval = 0; } public long getTimeOut() { return this.timeout; } public void setTimeOut(long timeout) { this.timeout = timeout; } public boolean available() { return ftDevice != null && ftDevice.isOpen(); } }