MT92220BG Zarlink Semiconductor, MT92220BG Datasheet - Page 126

• Manufacturer Part Number: MT92220BG
• Description: Description = 1023 Channel Voice Over IP/AAL2 Processor ;; Package Type = Epbga ;; No. Of Pins = 608
• Manufacturer: Zarlink Semiconductor

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A
B
HT
AR
RX HDLC
Stream/Buffer Index
HDLC Address
HDLC Control
Discharge Rate
Header Type
CRC
Maximum Bucket Fill
CBF
Last Packet Local Time
Stamp
I
Received Packet Count
Field
Clock Recovery channel A. When this field is set, an Adaptive Clock Recovery RTP
Event Structure using this packet’s sequence number and time stamp fields will be
written to the Adaptive clock recovery queue A.
Clock Recovery channel B. When this field is set, an Adaptive Clock Recovery RTP
Event Structure using this packet’s sequence number and time stamp fields will be
written to the Adaptive clock recovery queue B.
HDLC Encapsulation type. ‘0’ = HDLC Bit-wise; ‘1’ = HDLC Byte-wise.
Always Report Enable. Always generate an RX Disassembly Event Report Structure
when a packet is received and this field is set. Used for debugging only.
Index in the RX HDLC Stream/Buffer Control Table in SSRAM B.
Field that may be inserted in the HDLC packet header, depending on the Header
Type.
Field that may be inserted in the HDLC packet, depending on the Header Type.
Long term rate at which bytes can be received on this HDLC channel. The current
bucket fill is reduced at this rate. The rate is defined as a number of bytes per frame
that can be sent on the HDLC stream (including all forms of HDLC framing). This is a
floating point number; it has two bits of mantissa (excluding the hidden leading ‘1’)
and 4 bits of exponent. Zero is not a legal value. The minimum rate is 4 kbps, which is
defined as mantissa = “100” and exponent = “0001”. So to calculate the rate, the
following equation can be used: 4 kbps * (mantissa/8) * (2^exponent).
This can be set to:
"000"=Plain;
"001"=One byte address;
"010"=Two byte address;
"011"=One byte address + Control;
"100"=Two byte address + Control;
others = reserved.
‘0’ = no CRC bytes will be appended to the HDLC packet; ‘1’ = a 16-bit CRC-16
(otherwise known as CRC-CCITT) will be inserted at the end of the HDLC packet.
Up to this many bytes can be contained in the “policing bucket” of this HDLC channel
before packet discarding takes place. Largest value is 0x0000 (which means 65536
bytes), smallest value is 0x1 (which means 1 byte).
Current Bucket Fill. Current fill of the “policing bucket” in 1/64th of a byte. This field
should be initialized to all zeros by software.
Time stamp in frames of the last received packet used to determine the time delta
between the reception of HDLC packets. Used to discharge the Current Bucket Fill.
Initialized bit. Written to zero by software channel initialization. Written to ‘1’ by
hardware as soon at the first packet is received on this channel.
Total number of packets received on this channel so far. Every packet that gets to this
structure will be included.
Table 50 - Fields and Description
Zarlink Semiconductor Inc.
Description