Ack Packet Parameters; Ack Packet Bytes 0 &1 (Len); Ack Packet Bytes 2 & 3 (Type); Ack Packet Bytes 4 & 5 (Seq) - Digital Voice Systems Net-2000 User Manual

Net-2000™ Voice Codec Unit
User's Manual

Ack Packet Parameters

Ack Packet Bytes 0 &1 (len)
The len parameter (bytes 0 and 1) hold the 16-bit length of the packet (Table 3). The packet length is
eight bytes.
len = Length (in bytes) of total packet (including header)
Ack Packet Size

Table 41 len header parameter

Ack Packet Bytes 2 & 3 (type)
The type parameter (bytes 2 and 3) is 16-bits packet type and is always 0x0000 for ack packets.
type = Packet type
Ack

Table 42 type header parameter

Ack Packet Bytes 4 & 5 (seq)
Bytes 4 and 5 hold the 16-bit sequence number (see Table 5). The sequence number is used as a
method to detect if and when data packets are dropped, so it is important to ensure that consecutive
sequence numbers are transmitted for channel data packets during operation.
seq = Sequence number*
Minimum Value
Maximum Value

Table 43 seq header parameter

*Note: Sequence numbers should be incremented by one every time a packet is
transmitted. When the sequence number reaches 32767, the next valid sequence
number is -32768.
DVSI Confidential Proprietary
Byte 0
7 6 5 4 3 2 1 0
0 0 0 0 0 0 0 0
Byte 2
7 6 5 4 3 2 1 0
0 0 0 0 0 0 0 0
Byte 4
7 6 5 4 3 2 1 0
1 0 0 0 0 0 0 0
0 1 1 1 1 1 1 1
Section 3 – Net-2000™ VCU Control
Byte 1 Decimal
7 6 5 4 3 2 1 0
0 0 0 0 1 0 0 0
Byte 3
Hex Value
7 6 5 4 3 2 1 0
0 0 0 0 0 0 0 0
Byte 5 Decimal
7 6 5 4 3 2 1 0
0 0 0 0 0 0 0 0
1 1 1 1 1 1 1 1
Value
8 bytes
0x0000
Value
-32768
32767
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