
Arch
19 Wed May 28 17:36:23 1997
Draft 1/21/97
L64007 MPEG-2, DVB, JSAT Transport Demultiplexer Technical Manual
2-19
PRE.4 for Rev. D
Copyright 1997 by LSI Logic Corporation. All rights reserved.
Figure 2.15
Continuity Counter
Checking
Several exceptions to this rule are allowed, and the post-processing
block checks whether these exceptions occur when every packet integrity
error is detected. No packet lost error is triggered when there is a:
1.
Duplicate packet. (In this case, all duplicate packets are discarded.)
2.
Discontinuity Indicator (DI) in the adaptation eld set to one. (In this
case, the AF and payload are posted normally.)
3.
Packet with only an AF, but no payload.
2.3.2.2 Packet Lost Error Handling
Packet lost error occurs when CC mismatch has been detected and none
of the above exceptions are true. The host processor is notied with an
interrupt, indicating a loss-of-packet for this particular PID.
In case of audio or video PIDs, a packet lost error is propagated to the
downstream device (L64002 or L64005). Error propagation is done gen-
erating an error indicator to the A/V decoder by activating the AVERR pin
between the devices. If a packet lost error is triggered when processing
audio or video PIDs, the AVERR signal is asserted low when the rst
byte of the packet that triggered the error is sent to the L64007’s output
interface.
If a packet lost error occurs when the PID Post-processor processes PSI
sections, a “reset section storage” indicator is generated. This causes all
data stored as sections for this PID to be reset to the start position of
the last section.
H
PL
H
PL
H
PL
H
PL
PID = n
CC = 0
PID = n
CC = 1
PID = n
CC = 2
PID = n
CC = 4
H = Header
PL = Payload
Packet Lost Error
triggered