SPRUJ53B April 2024 – September 2024 TMS320F28P550SJ , TMS320F28P559SJ-Q1
In controller mode (CONTROLLER_PERIPHERAL = 1), the SPI provides the serial clock on the SPICLK pin for the entire serial communications network. Data is output on the SPIPICO pin and latched from the SPIPOCI pin.
The SPIBRR register determines both the transmit and receive bit transfer rate for the network. SPIBRR can select 125 different data transfer rates.
Data written to SPIDAT or SPITXBUF initiates data transmission on the SPIPICO pin, MSB (most-significant bit) first. Simultaneously, received data is shifted through the SPIPOCI pin into the LSB (least- significant bit) of SPIDAT. When the selected number of bits has been transmitted, the received data is transferred to the SPIRXBUF (buffered receiver) for the CPU to read. Data is stored right-justified in SPIRXBUF.
When the specified number of data bits has been shifted through SPIDAT, the following events occur:
In a typical application, the SPIPTE pin serves as a chip-enable pin for a SPI peripheral device. This pin is driven low by the controller before transmitting data to the peripheral and is taken high after the transmission is complete.
Figure 22-5 is a block diagram of the SPI in controller mode. The block diagram shows the basic control blocks available in SPI controller mode.