SPRUIU1C July 2020 – February 2024 DRA821U , DRA821U-Q1
Turbo mode improves the throughput of the MCSPI interface when a single channel is enabled by allowing transfers until the shift register and the MCSPI_RX_0/1/2/3 register are full. Turbo mode is time saving when a transfer exceeds two words. This mode is programmable per channel (through the MCSPI_CHCONF_0/1/2/3[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 12.1.5.4.3.2, Controller Transmit-and-Receive Mode (Full Duplex)). An enabled channel can be scheduled if its receive register is full (the MCSPI_CHSTAT_0/1/2/3[0] RXS bit) when the shift-register is assigned until the shift register is full.
The MCSPI_RX_0/1/2/3 register cannot be overwritten in turbo mode. Consequently, the MCSPI_IRQSTATUS[3] RX0_OVERFLOW bit is never set in this mode.