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packet converter with x-mac and crc support

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fros4943 2008-10-29 18:28:16 +00:00
parent d6fff91861
commit 6ae7fc99a1
1 changed files with 135 additions and 28 deletions
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163
tools/cooja/apps/mspsim/src/se/sics/cooja/mspmote/interfaces/CC2420RadioPacketConverter.java
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@ -26,7 +26,7 @@
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $Id: CC2420RadioPacketConverter.java,v 1.3 2008/06/27 14:11:52 nifi Exp $
* $Id: CC2420RadioPacketConverter.java,v 1.4 2008/10/29 18:28:16 fros4943 Exp $
*/
package se.sics.cooja.mspmote.interfaces;
@ -34,44 +34,151 @@ package se.sics.cooja.mspmote.interfaces;
import org.apache.log4j.Logger;
import se.sics.cooja.COOJARadioPacket;
import se.sics.cooja.RadioPacket;
/**
* Converts radio packets between CC24240/Sky and COOJA.
* Converts radio packets between X-MAC/CC24240/Sky and COOJA.
* Handles radio driver specifics such as length header and CRC footer.
*
* @author Fredrik Osterlind
* @author Fredrik Österlind
*/
public class CC2420RadioPacketConverter {
private static Logger logger = Logger.getLogger(CC2420RadioPacketConverter.class);
/* CC2420/802.15.4 packet: PREAMBLE(4) _ SYNCH(2) _ LENGTH(1) _ PAYLOAD(<27) _ CRCFOOTER(2) */
public static final boolean WITH_PREAMBLE = true;
public static final boolean WITH_SYNCH = true;
public static final boolean WITH_XMAC = true;
public static final boolean WITH_CHECKSUM = true;
public static final boolean WITH_TIMESTAMP = true;
public static final boolean WITH_FOOTER = true;
/**
* Converts a COOJA radio packet to a CC2420 radio packet.
*
* @param coojaPacket COOJA radio packet
* @return CC2420 radio packet
*/
public static CC2420RadioPacket fromCoojaToCC24240(RadioPacket coojaPacket) {
byte[] data = coojaPacket.getPacketData();
byte[] cc2420Data = new byte[data.length + 3];
cc2420Data[0] = (byte) ((data.length + 2) & 0xff);
System.arraycopy(data, 0, cc2420Data, 1, data.length);
return new CC2420RadioPacket(cc2420Data);
public static byte[] fromCoojaToCC24240(COOJARadioPacket packet) {
byte cc2420Data[] = new byte[6+127];
int pos = 0;
byte packetData[] = packet.getPacketData();
byte len; /* total packet minus preamble(4), synch(1) and length(1) */
short accumulatedCRC = 0;
/* 4 bytes preamble */
if (WITH_PREAMBLE) {
cc2420Data[pos++] = 0;
cc2420Data[pos++] = 0;
cc2420Data[pos++] = 0;
cc2420Data[pos++] = 0;
}
/**
* Converts a CC2420 radio packet to a COOJA radio packet.
*
* @param cc2420RadioPacket CC24240 radio packet
* @return COOJA radio packet
*/
public static COOJARadioPacket fromCC2420ToCooja(CC2420RadioPacket cc2420RadioPacket) {
byte[] cc2420Data = cc2420RadioPacket.getPacketData();
byte[] data = new byte[cc2420Data.length - 3];
System.arraycopy(cc2420Data, 1, data, 0, data.length);
return new COOJARadioPacket(data);
/* 1 byte synch */
if (WITH_SYNCH) {
cc2420Data[pos++] = 0x7A;
}
/* 1 byte length */
len = (byte) packetData.length;
if (WITH_XMAC) {
len += 4;
}
if (WITH_CHECKSUM) {
len += 2;
}
if (WITH_TIMESTAMP) {
len += 3;
}
if (WITH_FOOTER) {
len += 2;
}
cc2420Data[pos++] = len;
/* (TODO) 4 byte X-MAC */
if (WITH_XMAC) {
cc2420Data[pos++] = 0;
accumulatedCRC = CRCCoder.crc16Add((byte)0, accumulatedCRC);
cc2420Data[pos++] = 0;
accumulatedCRC = CRCCoder.crc16Add((byte)0, accumulatedCRC);
cc2420Data[pos++] = 0;
accumulatedCRC = CRCCoder.crc16Add((byte)0, accumulatedCRC);
cc2420Data[pos++] = 0;
accumulatedCRC = CRCCoder.crc16Add((byte)0, accumulatedCRC);
}
/* Payload */
for (byte b : packetData) {
accumulatedCRC = CRCCoder.crc16Add(b, accumulatedCRC);
}
System.arraycopy(packetData, 0, cc2420Data, pos, packetData.length);
pos += packetData.length;
/* 2 bytes checksum */
if (WITH_CHECKSUM) {
cc2420Data[pos++] = (byte) (accumulatedCRC & 0xff);
cc2420Data[pos++] = (byte) ((accumulatedCRC >> 8) & 0xff);
}
/* (TODO) 3 bytes timestamp */
if (WITH_TIMESTAMP) {
cc2420Data[pos++] = 0;
cc2420Data[pos++] = 0;
cc2420Data[pos++] = 0;
}
/* (TODO) 2 bytes footer */
if (WITH_FOOTER) {
cc2420Data[pos++] = 0; /* RSSI */
cc2420Data[pos++] = (byte) 0x80; /* CRC and CORRELATION */
}
byte cc2420DataStripped[] = new byte[pos];
System.arraycopy(cc2420Data, 0, cc2420DataStripped, 0, pos);
/*logger.info("Data length: " + cc2420DataStripped.length);*/
return cc2420DataStripped;
}
public static COOJARadioPacket fromCC2420ToCooja(byte[] data) {
int pos = 0;
int len; /* Payload */
/* Use some CC2420/MAC specific field such as X-MAC response */
/* (IGNORED) 4 bytes preamble */
if (WITH_PREAMBLE) {
pos += 4;
}
/* (IGNORED) 1 byte synch */
if (WITH_SYNCH) {
pos += 1;
}
/* 1 byte length */
len = data[pos];
pos += 1;
/* (IGNORED) 4 byte X-MAC */
if (WITH_XMAC) {
pos += 4;
len -= 4;
}
/* (IGNORED) 2 bytes checksum */
if (WITH_CHECKSUM) {
len -= 2;
}
/* (IGNORED) 3 bytes timestamp */
if (WITH_TIMESTAMP) {
len -= 3;
}
/* (IGNORED) 2 bytes footer */
if (WITH_FOOTER) {
len -= 2;
}
/*logger.info("Payload pos: " + pos);
logger.info("Payload length: " + len);*/
byte coojaData[] = new byte[len];
System.arraycopy(data, pos, coojaData, 0, len);
return new COOJARadioPacket(coojaData);
}
}