SPRUJ53B April 2024 – September 2024 TMS320F28P550SJ , TMS320F28P559SJ-Q1
The FSI supports a SPI compatibility mode. While the FSI can communicate with a standard SPI module, the FSI supports a limited configuration. The features of this compatibility mode are:
Table 25-12 lists the frame structure of the FSI-SPI compatibility mode. Each frame phase is present in this mode. If the FSI is transmitting to a standard SPI module, the SPI must decode the frame structure. Similarly, if the FSI is configured as a SPI peripheral, the standard SPI must encode the transmission to be sent.
Idle State | Start of Frame | Frame Type | User Data | Data Words | CRC byte(1) | Frame Tag | End of Frame | Idle State |
---|---|---|---|---|---|---|---|---|
1001 | 4 bits | 8 bits | 1-16 words | 8 bits | 4 bits | 0110 |
Because of the requirement that the standard SPI module encodes the various frame data, this limits the type of modules that can be connected to the FSI in SPI mode. The paired SPI module must have enough functionality to encode and decode the frames.
If the FSI is transmitted to a standard 16-bit SPI, the data is arranged in the following manner. The example provided in Table 25-13 assumes a DATA_2_WORD frame has been sent.
SPI Data | Data Contents |
---|---|
SPI word 0 | 1001, 0100, 8-bit User Data |
SPI word 1 | Data word 1 |
SPI word 2 | Data word 2 |
SPI word 3 | 8-bit CRC, 4-bit Frame Tag, 0110 |