SPRUIV7B May 2022 – September 2023 AM620-Q1 , AM623 , AM625 , AM625-Q1 , AM625SIP
The MCASP transmit formatting unit consists of three stages :
Figure 12-16 shows the transmit formatting unit.
The MCASP transmitter supports serial formats of:
Hardware support for these serial formats comes from the programmable options in the bitstream format register - MCASP_XFMT:
As shown in Figure 12-16, the data to the transmit format unit can come from the configuration port (CFG) or the data port (DATA). The selection is made through the MCASP_XFMT[3] XBUSEL bit. According to port type selected, data transfer has different behaviour. For more details, refer to the Section 12.1.1.4.10.1.3, Transfers Through the DATA Port, and Section 12.1.1.4.10.1.4, Transfers Through the Configuration (CFG) Bus.
In the transmit format unit (TFU), the input data bits are first masked-off with the MCASP_XMASK[31-0] XMASK contents. The masked data is then right-rotated to the MCASP_XFMT[2-0] XROT bit field positions, to produce the output word for a TDM- or DIT- transmission.
The bit mask stage includes a full 32-bit mask register, allowing selected individual bits to pass through the stage unchanged or be masked off.