SPRUJ28E November 2021 – September 2024 AM68 , AM68A , TDA4AL-Q1 , TDA4VE-Q1 , TDA4VL-Q1
Table 12-320 shows the configuration of the MCASP using the DMA method for reception. Possible interrupt error event servicing is also considered. shows the initial setup for DMA - based transmission.
Because of the DATA port burst access capability with the DMA method, it is strongly recommended that DMA transfers are initiated through the MCASP DATA port.
Step | Register/Bit Field/Programming Model | Value |
---|---|---|
Recommended: Select DATA port to access the transmit buffers. | MCASP_RFMT[3] RBUSEL | 0x0 |
Enable the Rx DMA requests generation. | MCASP_PIDTCTL[0] RDATDMA | 0x0 |
Enable the Rx DMA error event, because of MCASP DATA port usage. | MCASP_RINTCTL[3] RDMAERR | 0x1 |
Optional: Enable the receive error event interrupts. | MCASP_RINTCTL[2] RCKFAIL MCASP_RINTCTL[1] RSYNCERR MCASP_RINTCTL[0] ROVRN | 0x1 0x1 0x1 |
Optional: Enable the start of frame interrupt. Optional: Enable the last slot data interrupt. | MCASP_RINTCTL[7] RSTAFRM MCASP_RINTCTL[4] RLAST | 0x1 0x1 |
Disable the data ready event receive interrupt, as DMA is used to service this request. | MCASP_RINTCTL[5] RDATA | 0x0 |
DMA startup reception procedure. This procedure is identical than the one shown in Figure 12-284. The only difference is that DMA automatically services all the RINT events raised by the MCASP, and no CPU data processing intervention is required. The CPU is involved only in error handling shown in Figure 12-286. | See Figure 12-284. |