SPRUJ53B April 2024 – September 2024 TMS320F28P550SJ , TMS320F28P559SJ-Q1
The Block Write (Figure 27-8) protocol is similar to Write Word in structure, except that there are more than 2 data bytes in the message. Following the receipt of the command byte, the block length and 2 data bytes, the PMBus module provides a data ready interrupt. The module waits for the firmware to read the received data and program the acknowledge register. While waiting for an ACK from the firmware, the module drives the clock line low, stalling the bus. The data ready interrupts continue for the duration of the message at a frequency of every 4 data bytes. The number of bytes received can be found within the PMBSTS register. At the end of the message, less than 4 bytes can be stored in the PMBRXBUF register. The PEC Valid bit can be checked to determine if the received PEC value is accurate.