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Dual tdm channel example -6 – Motorola MPC8260 User Manual

Page 460

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14-6

MPC8260 PowerQUICC II UserÕs Manual

MOTOROLA

Part IV. Communications Processor Module

At its most ßexible, the TSA can provide four separate TDM channels, each with
independent receive and transmit routing assignments and independent sync pulse and
clock inputs. Thus, the TSA can support eight, independent, half-duplex TDM sources, four
in reception and four in transmission, using eight sync inputs and eight clock inputs.
Figure 14-3 shows a dual-channel example.

Figure 14-3. Dual TDM Channel Example

In addition to channel programming, the TSA supports up to four strobe outputs that may
be asserted on a bit or byte basis. These strobes are completely independent from the
channel routing used by the SCCs and SMCs. The strobe outputs are useful for interfacing
to other devices that do not support the multiplexed interface or for enabling/disabling
three-state I/O buffers in a multiple-transmitter architecture. Notice that open-drain
programming on the TXDx pins that supports a multiple-transmitter architecture occurs in
the parallel I/O block. These strobes can also be used for generating output wave forms to
support such applications as stepper-motor control.

Most TSA programming is done in the two 256-

´ 16-bit SIx RAMs. These SIx RAMs are

directly accessible by the core in the internal register section of the MPC8260 and are not

SCC3

SMC1

TDMa Rx

TSA

TDMa

TDMb

TDMa Tx SYNC

TDMa Tx CLOCK

SCC2

SMC1

SCC2

TDMa Rx Sync

TDMa Rx Clock

TDMa Rx

SCC3

SCC4

TDMa Tx

TDMb Tx Sync

TDMb Tx Clock

TDMb Rx Sync

TDMb Rx Clock

SCC2

SMC1

TDMb Rx

Note:
SCCs can receive on one TDM and transmit on another (SCC2 and SCC3).