public int Encode(ref byte[] buf, ref BACNET_ADDRESS dest, ref BACNET_NPDU_DATA npdu, int pdu_len)
{
UInt16 BVLC_length = 0;
byte[] data = new byte[1024];
Array.Copy(buf, 0, data, 4, pdu_len);
buf = data;
buf[0] = 0x81; //BVLL_TYPE_BACNET_IP
if (dest.net == 0xFFFF) //全局广播
{
buf[1] = (byte)BACNET_BVLC_FUNCTION.BVLC_DISTRIBUTE_BROADCAST_TO_NETWORK;
}
else if (dest.mac_len == 0)
{
buf[1] = (byte)BACNET_BVLC_FUNCTION.BVLC_ORIGINAL_BROADCAST_NPDU;
}
else if (dest.mac_len == 6)
{
buf[1] = (byte)BACNET_BVLC_FUNCTION.BVLC_ORIGINAL_UNICAST_NPDU;
}
BVLC_length = (UInt16)(pdu_len + 4);
BasicalProcessor.Encode_Unsigned16(ref buf, BVLC_length, 2);
return(BVLC_length);
}
public static void Get_Broadcast_Address(ref BACNET_ADDRESS dest_address, Boolean local, UInt16 port)
{
dest_address.net = 0;
dest_address.len = 6;
for (int u = 0; u < 7; u++)
{
dest_address.adr[u] = 0;
}
dest_address.mac_len = 6;
for (int i = 0; i < 4; i++)
{
dest_address.mac[i] = 255;
}
BasicalProcessor.Encode_Unsigned16(ref dest_address.mac, port, 4);
if (!local)
{
dest_address.net = 0xFFFF; //远程广播
}
}
public static void Get_My_Address(ref BACNET_ADDRESS my_address)
{
my_address.net = 0;
my_address.len = 6;
for (int i = 0; i < 7; i++)
{
}
my_address.mac_len = 6;
my_address.mac[0] = 192;
my_address.mac[1] = 168;
my_address.mac[2] = 110;
my_address.mac[3] = 1;
BasicalProcessor.Encode_Unsigned16(ref my_address.mac, 50, 4);
my_address.adr[0] = 192;
my_address.adr[1] = 168;
my_address.adr[2] = 110;
my_address.adr[3] = 1;
BasicalProcessor.Encode_Unsigned16(ref my_address.adr, 50, 4);
//测试用
}
public int Encode(ref byte[] npdu, ref BACNET_ADDRESS dest, ref BACNET_ADDRESS src, ref BACNET_NPDU_DATA npdu_data, int pos = 0)
{
int len = 0; /* return value - number of octets loaded in this function */
byte i = 0; /* counter */
if (npdu != null)
{
npdu[pos + 0] = npdu_data.protocol_version;
//控制号
npdu[pos + 1] = 0;
//控制信息
if (npdu_data.network_layer_message)
{
npdu[pos + 1] |= BacnetConst.BIT7;
}
//是否是网络型报文
if (dest.net != null)
{
npdu[pos + 1] |= BacnetConst.BIT5;
}
//0 表示DNET DLEN DADR HPO COUNT不存在
// 1 表示都存在，
if (src.len != 0)
{
npdu[pos + 1] |= BacnetConst.BIT3;
}
//0代表SNET SLEN 和SADR都不存在
// 1表示都存在
if (npdu_data.data_expecting_reply)
{
npdu[pos + 1] |= BacnetConst.BIT2;
}
//是否需要回复
npdu[pos + 1] |= (byte)((byte)npdu_data.priority & 0x03);
//优先级
len = 2;
if (dest.len != 0)
{
len += BasicalProcessor.Encode_Unsigned16(ref npdu, dest.net, pos + len);
npdu[pos + len] = dest.len;
len++;
//当DNET=FFFF 表示全局广播
//缺省表示本地广播
if (dest.len != 0)
{
for (i = 0; i < dest.len; i++)
{
npdu[pos + len++] = dest.adr[i];
}
}
}
if (src.len != 0)
{
len += BasicalProcessor.Encode_Unsigned16(ref npdu, src.net, pos + len);
npdu[pos + len] = src.len;
len++;
if (src.len != 0)
{
for (i = 0; i < src.len; i++)
{
npdu[pos + len++] = src.adr[i];
}
}
}
if (dest.net != 0)
{
npdu[pos + len] = (byte)npdu_data.hop_count;
len++;
//转发计数
}
if (npdu_data.network_layer_message)
{
npdu[pos + len] = (byte)npdu_data.network_message_type;
len++;
if ((int)npdu_data.network_message_type >= 0x80)
{
len += BasicalProcessor.Encode_Unsigned16(ref npdu, npdu_data.vendor_id, pos + len);
}
//报文类型
//0x80以后为用户扩展类型
}
}
return(len);
}
