Serial Interface with Time-Slot Assigner
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
15-6 Freescale Semiconductor
At its most flexible, 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 15-3 shows a dual-channel example.
Figure 15-3. 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 i n a multiple-tr ansmitter architecture . Notice tha t
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 directl y
accessible by the core in the internal register section of the PowerQUICC II and are not associated with
the dual-port RAM. One SIx RAM is always used to program the transmit routing; the other is always used
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).