public static Gb645MeterPacket getPacket(byte[] msg, int headIndex) {
if (Gb645MeterPacket.getMsgHeadOffset(msg, headIndex) == headIndex) {
Gb645MeterPacket pack = new Gb645MeterPacket("0");
pack.address.setValue(msg, headIndex + 1);
pack.controlCode.setValue(msg[headIndex + 8]);
int len = BcdUtils.byteToUnsigned(msg[headIndex + 9]);
pack.setDataBytes(msg, headIndex + 10, len);
return pack;
} else {
return null;
}
}
public static int getMsgHeadOffset(byte[] msg, int firstIndex) {
int head = Gb645MeterPacket.getHeadOffset(msg, firstIndex);
while (head != -1) {
int len = BcdUtils.byteToUnsigned(msg[head + 9]);
if (msg[head + len + 11] == 0x16) {
if (Gb645MeterPacket.calcCs(msg, head, len + 10) == msg[head + len + 10]) {
return head;
}
}
firstIndex = head + 1;
head = Gb645MeterPacket.getHeadOffset(msg, firstIndex);
}
return -1;
}