pxf4333 Infineon Technologies Corporation, pxf4333 Datasheet - Page 121

• Manufacturer Part Number: pxf4333
• Description: Abm 3g Atm Buf Fer Manager
• Manufacturer: Infineon Technologies Corporation

4.3
Teardown of Queues
Disabling a queue via the queue-disable bit does not clear the cells in the queue, but:
• The acceptance of the queue for new cells is disabled
• The queue is still served, but the cells are discarded internally
Normally, at the time a queue is cleared, there will be no more cells in the queue. This
can be checked by reading the queue length. In case of a highly filled queue which is
served slowly, the time to empty the queue could be long. To deplete the queue more
quickly, its weight can be increased temporarily. However, because the discarded cells
produce idle times on the UTOPIA output, the chosen weight factor should not be too
high.
4.4
Refer to
4.4.1
First, the header octets are assembled from the VPI, VCI and/or LCI and written to the
corresponding registers
CPCS-UU and CPI are also provided to register UA5TXTR/DA5TXTR. The packet
payload length is written to
Four octets of payload are written to the two data registers
and UA5TXDAT1/DA5TXDAT1. The Status register
read afterwards to check the current state of the assembly unit. The assembly of the cells
is done without interaction of the microprocessor.
4.4.2
If an AAL5 interrupt indicates that an AAL5 packets has arrived first the cell header
should be read. Before each access to the data registers the status register
DA5SARS
As long as the AAL5 status register does not indicate End of Packet (PE), the payload
can be received from the data registers
DA5RXDAT1. This data registers should always be read together. If the PE flag is set
the next read accesses to the both data registers will return the last payload octets. After
this access the Status register still contains the PE flag but additionally a length
information of the packet stored in the OV flags. Again the data registers are read to get
the trailer of the packet (CPCS-UU and CPI) and the Status Byte. Depending on the
packet length there are four possibilities for the mapping of these octets to the two data
registers, indicated by the OV flags. The four cases are depicted in
Data Sheet
Chapter 3.2.3
should be read to get the current status of the extraction unit.
Connection Teardown Example
AAL5 Packet Insertion/Extraction
AAL5 Packet Insertion
AAL5 Packet Extraction
for a more general description.
UA5TXHD0/DA5TXHD0
UA5TXCMD/DA5TXCMD
UA5RXDAT0/DA5RXDAT0
121
and UA5TXHD1/DA5TXHD1. The
UA5SARS/DA5SARS
together with the AAL5EN flag.
UA5TXDAT0/DA5TXDAT0
Operational Description
Figure
and
PXF 4333 V1.1
UA5RXDAT1/
4-10.
UA5SARS/
should be
2001-12-17
ABM-3G