
Agere Systems Inc.
147
Data Sheet
May 2001
and Packet Payload Engine
Ambassador T8110 PCI-Based H.100/H.110 Switch
14
Connection Control—Standard and Virtual Channel
(continued)
Each of these connection memory pages are initialized at reset (valid bit entries are reset to invalid). Additionally,
each page may be initialized individually via software command, RESET PAGE (refer to Figure 35 on page 136
and Figure 42 on page 141).
For standard telephony switching connections, the connection memory locations contain one-half simplex switch
control information (refer to Figure 36 on page 137 and Figure 43 on page 141), as follows:
n
VALID bit indicates that a valid switch connection exists for this stream/time-slot.
n
VTC indicates whether the connection is a virtual channel connection or a telephony connection. A 0 denotes a
telephony connection.
n
RWS indicates whether the connection is
from
(from serial stream to data memory) or
to
(from DATA memory to
serial stream).
n
VFC (virtual framing control) controls which data page is used in double-buffer scenarios.
Note:
There are three data memory configurations that allow double-buffering of the data, in order to create con-
stant frame delay connections. Refer to Section 14.2.1.2 on page 148 and Section 14.2.2.1 on page 149.
n
PME indicates a pattern mode connection.
n
TAG is the data memory location used for this one-half simplex switch connection (or the data pattern sent to
serial output for pattern mode connections).
n
SUBRATE information is subrate switching control (bitswap).
For virtual channel (packet payload) switching connections, there are two possible control fields, depending on
whether the virtual channel is nonbonded (refer to Figure 37) or bonded (refer to Figure 38).
14.2.1.1.1 Virtual Channel Switching, Nonbonded Connections
n
VALID bit indicates that a valid switch connection exists for this stream/time slot.
n
VTC indicates whether the connection is a virtual channel connection or a telephony connection. A 1 denotes a
virtual channel connection.
n
RWS indicates whether the connection is
from
(from serial stream to data memory) or
to
(from DATA memory to
serial stream).
n
BVF is bonded virtual frame marker (unused for nonbonded channels).
n
BCC is bonded channel control indicator; 0 denotes a nonbonded channel.
n
VC identifier and VCP indicates which virtual channel this information is for (0 up to 511 virtual channels).
n
SVF (subrate virtual frame marker) is an indicator for the last piece of a packed subrate byte.
n
SUBRATE information is subrate switching control (bitswap); refer to Section 14.2.2.3.
14.2.1.1.2 Virtual Channel Switching, Bonded Connections
n
VALID bit indicates that a valid switch connection exists for this stream/time slot.
n
VTC indicates whether the connection is a virtual channel connection or a telephony connection. A 1 denotes a
virtual channel connection.
n
RWS indicates whether the connection is
from
(from serial stream to data memory) or
to
(from data memory to
serial stream).
n
BVF (bonded virtual frame marker) is an indicator for the last byte switched in a frame.