Motorola MPC8260 - Manual (Page 821)

29-41 MPC8260 PowerQUICC II UserÕs Manual MOTOROLA
Part IV. Communications Processor Module
29.10.1.3 Global Mode Entry (GMODE)
Figure 29-23 shows the layout of the global mode entry (GMODE).
Table 29-14 describes GMODE Þelds.
29.10.2 Connection Tables (RCT, TCT, and TCTE)
The receive and transmit connection tables, RCT and TCT, store host-initialized connection
parameters after connection set-up. These include AAL type, connection trafÞc parameters,
BD parameters and temporary parameters used during segmentation and reassembly
(SAR). The transmit connection table extension (TCTE) supports special connections that
Bits 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Field 0 0 0 0 0 0 ALB CTB REM 0 0 UEAD CUAB EVPT 0 ALM
Figure 29-23. Global Mode Entry (GMODE)
Table 29-14. GMODE Field Descriptions
Bits Name Description
0Р5 С Reserved, should be cleared.
6 ALB Address look up bus for CAM or address compression tables
0 Reside on the 60x bus.
1 Reside on the local bus.
7 CTB External connection tables bus
0 Reside on the 60x bus.
1 Reside on the local bus.
8 REM Receive emergency mode
0 Enable REM operation. When the receive FIFO is full, the ATM transmitter stops sending
data cells until the receiver emergency state is cleared (FIFO not full). The transmitter pace
is maintained, although a small CDV may be introduced. This mode enables the receiver to
receive bursts of cells above the steady state performance.
1 Disable REM operation. Note that to check system performance the user may want to set
this bit.
9Р10 С Reserved, should be cleared.
11 UEAD User-deÞned cells extended address mode. See Section 29.7.1, ÒUDC Extended Address
Mode (UEAD).Ó
0 Disable UEAD mode.
1 Enable UEAD mode.
12 CUAB Check unallocated bits
0 Do not check unallocated bits during address compression.
1 Check unallocated bits during address compression.
13 EVPT External address compression VP table
0 VP table resides in dual-port RAM.
1 VP table reside in external memory.
14 Ñ Reserved, should be cleared.
15 ALM Address look-up mechanism. See Section 29.4, ÒVCI/VPI Address Lookup Mechanism.Ó
0 External CAM lookup.
1 Address compression.