SPRUJ52E June 2022 – September 2025 AM69 , AM69A , TDA4AH-Q1 , TDA4AP-Q1 , TDA4APE-Q1 , TDA4VH-Q1 , TDA4VP-Q1 , TDA4VPE-Q1
The MCASP supports a burst transfer mode, which is useful for nonaudio data such as passing control information between two processors. Burst transfer mode uses a synchronous serial format similar to the TDM mode. The frame sync generation is not periodic or time-driven as in TDM mode, but data driven, and the frame sync is generated for each data word transferred.
When operating in burst frame sync mode (see Figure 12-345), as specified for transmit (MCASP_AFSXCTL[15-7] = 0 ) and receive (MCASP_AFSRCTL[15-7] RMOD = 0), one slot is shifted for each active edge of the frame sync signal that is recognized. Additional clocks after the slot and before the next frame sync edge are ignored.
In burst frame sync mode, the frame sync delay may be specified as 0, 1, or 2 serial clock cycles. This is the delay between the frame sync active edge and the start of the slot. The frame sync signal lasts for a single bit clock duration (MCASP_AFSRCTL[4] FRWID = 0, MCASP_AFSXCTL[4] FXWID = 0).
For transmit, when generating the transmit frame sync internally, the frame sync begins when the previous transmission has completed and when all the XBUFn (for every serializer set to operate as a transmitter) has been updated with new data.
For receive, when generating the receive frame sync internally, frame sync begins when the previous transmission has completed and when all the RBUFn (for every serializer set to operate as a receiver) has been read.
Figure 12-345 Burst Frame Sync ModeThe control registers must be configured as follows for the burst transfer mode. The burst mode specific bit fields are in bold face: