7.3 Firmware Command Format
The following frame format is used for firmware commands, where the PL360 device supports an address of two bytes.
The address field contains the identification number of the region to access data. These region numbers are described in Firmware Data Memory Regions.
The CMD field (1 bit), which is the most significant bit of the length field, contains the SPI command:
- Read command: 0
- Write command: 1
The length field (15 bits) contains the number of 16-bit blocks to read.
The payload field depends on the region number to access and on the communication stack in use, G3 or PRIME. For further information, refer to atpl360_comm.h file.