CN8236EBGB Mindspeed Technologies, CN8236EBGB Datasheet - Page 99

• Manufacturer Part Number: CN8236EBGB
• Description: ATM SAR 155Mbps 3.3V ABR/CBR/GFR/UBR/VBR 388-Pin BGA
• Manufacturer: Mindspeed Technologies

Specifications of CN8236EBGB

• Package: 388BGA
• Traffic Class: ABR|CBR|GFR|UBR|VBR
• Utopia Type: Level 1|Level 2
• Host Interface: PCI
• Maximum Data Rate: 155 Mbps
• Typical Operating Supply Voltage: 3.3 V
• Minimum Operating Supply Voltage: 3 V

CN8236
ATM ServiceSAR Plus with xBR Traffic Management
Table 4-13. Segmentation Buffer Descriptor Field Descriptions (2 of 3)
28236-DSH-001-B
AAL_OPT
CELL
BOM
EOM
LENGTH
GFC_DATA
WR_GFC
WR_PTI
WR_VCI
PTI_DATA
VCI_DATA
NEW_VCI
Field Name
Options for AAL_MODE:
For AAL_MODE = AAL0
00 = Normal operation
01 = SINGLE
10 = Reserved
11 = Reserved
For AAL_MODE = AAL3/4 or AAL5
00 = Normal operation
01 = ABORT
SINGLE: LENGTH is ignored and 48-octets are read from buffer to form the payload of a single ATM
cell. VCC table entry CRC_REM, BUFF_LENGTH, and PDU_LENGTH are not affected. By using the
LINK_HEAD bit in the transmit entry, the buffer descriptor is linked at the start of buffer descriptor
chain for VCC. This means that there are no concerns with mid-cell insertion and that the cell has low
latency. This is intended for OAM cells.
NOTE: This option MUST be set in the buffer descriptor for any Tx Queue entry with LINK_HEAD set.
To do otherwise may result in corrupted SEG data.
ABORT: Send AAL3/4 or AAL5 ABORT cell (no data is read from segmentation buffer). A buffer that
has both ABORT and BOM set is returned without sending an abort cell.
0 = CN8236 reads the 48-octet payload of ATM cells from memory and generates the ATM header internally.
1 = The CN8236 reads the entire 52-octet ATM cell from segmentation buffer. The ATM_HEADER
1 = Buffer contains the beginning of a message. (See
1 = Buffer contains the end of a message. (See
Number of bytes of data contained in the segmentation buffer. Local memory, non-EOM buffer lengths
must be multiples of 4 bytes (mod 4). Maximum allowable size is 64 KB.
Data for WR_GFC option.
0 = The CN8236 generates the GFC field from the VCC table entry ATM_HEADER field.
1 = The CN8236 overwrites the ATM header GFC field for all cells in the buffer with GFC_DATA.
Global GFC changes (active for all buffers of VCC) can be set in the VCC table entry ATM header.
This bit is active only when HEADER_MOD is set.
0 = The CN8236 generates the PTI field from the VCC table entry ATM_HEADER field.
1 = The CN8236 overwrites the ATM header PTI field for all cells in the buffer with PTI_DATA.
The host can use this feature to generate F5 and PM OAM cells. (See
This bit is active only when HEADER_MOD is set.
This bit disables PM TUC and BIP16 calculations.
0 = The CN8236 generates the VCI field from the VCC table entry ATM_HEADER field.
1 = The CN8236 overwrites the ATM header VCI field for all cells in the buffer with
(0x0000|VCI_DATA). (MSBs of VCI are set to 0.)
Used to generate F4 OAM cells. (See
This bit is active only when HEADER_MOD is set.
This bit disables PM TUC and BIP16 calculations.
Data for WR_PTI option. Normally used to generate OAM cells.
Data for WR_VCI option. Normally used to generate OAM cells.
Data for the RPL_VCI. The CN8236 overwrites the VCC table entry ATM_HEADER VCI field with this
data. Therefore, the effect is permanent until the next buffer descriptor with RPL_VCI is processed.
stored in the VCC table entry is not used in this mode, and AAL_MODE is ignored.
Mindspeed Technologies
Chapter
Description
7.0.)
Table
4-1.)
Table
™
4.3 Segmentation Control and Data Structures
4-1.)
4.0 Segmentation Coprocessor
Chapter
7.0.)
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