SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
Turbo mode improves the throughput of the SPI interface when a single channel is enabled by allowing transfers until the shift register and the MCSPI_RXx register are full. Turbo mode is time saving when a transfer exceeds two words. This mode is programmable per channel (through the SPI1.MCSPI_CHxCONF[9] TURBO bit).
When several channels are enabled, the TURBO bit has no effect and the channel access to the shift registers remains as previously described.
In turbo mode, Rule 1 and Rule 2 apply, but Rule 3 does not (see Section 26.4.4.3.2, Master Transmit-and-Receive Mode (Full Duplex)). An enabled channel can be scheduled if its receive register is full (the MCSPI_CHxSTAT[0] RXS bit) when the shift-register is assigned until the shift register is full.
The MCSPI_RXx register cannot be overwritten in turbo mode. Consequently, the MCSPI_IRQSTATUS[3] RX0_OVERFLOW bit is never set in this mode.