Motorola MPC8260 - Manual (Page 463)

MOTOROLA Chapter 14. Serial Interface with Time-Slot Assigner 14-9
Part IV. Communications Processor Module
14.4.1 One Multiplexed Channel with Static Frames
The example in Figure 14-5 shows one of many possible settings. With this conÞguration,
the SIx RAM has 256 entries for transmit data and strobe routing and 256 entries for receive
data and strobe routing. This conÞguration should be chosen only when one TDM is
required and the routing on that TDM does not need to be dynamically changed. The
number of entries available in the SIx RAM is determined by the user.
Figure 14-5. One TDM Channel with Static Frames and Independent Rx and Tx
Routes
14.4.2 One Multiplexed Channel with Dynamic Frames
In the conÞguration shown in Figure 14-6, one multiplexed channel has 256 entries for
transmit data and strobe routing and 256 entries for receive data and strobe routing. Each
RAM has two sections, the current-route RAM and a shadow RAM for changing serial
routing dynamically.
After programming the shadow RAM, the user sets SIxCMDR[CSRxn] for the associated
channel. When the next frame sync arrives, the SI automatically exchanges the current-
route RAM for the shadow RAM. See Section 14.4.5, ÒStatic and Dynamic Routing.Ó
256 Entries
TXa
Route
Framing Signals
L1TCLKax
L1TSYNCax
SIx RAM address:
256 Entries
RXa
Route
511
1535
1024
L1RCLKax
L1RSYNCax
(16 bits wide)
0