SPRUHM9H October 2014 – May 2024 TMS320F28075 , TMS320F28075-Q1 , TMS320F28076
If you want to use more than 32 channels, you can change which channel blocks are assigned to partitions A and B during the course of a data transfer. However, these changes must be carefully timed. While a partition is being transferred, the associated block assignment bits cannot be modified and the associated channel enable register cannot be modified. For example, if block 3 is being transferred and block 3 is assigned to partition A, you cannot modify (R/X)PABLK to assign different channels to partition A, nor (R/X)CERA to change the channel configuration for partition A.
Several features of the McBSP help you time the reassignment:
Figure 20-33 shows an example of reassigning channels throughout a data transfer. In response to a frame-synchronization pulse, the McBSP alternates between partitions A and B. Whenever partition B is active, the CPU changes the block assignment for partition A. Whenever partition A is active, the CPU changes the block assignment for partition B.
Figure 20-33 Reassigning Channel Blocks
Throughout a McBSP Data Transfer