SPRUIU1C July 2020 – February 2024 DRA821U , DRA821U-Q1
Each ring contains four memory spaces on the VBUSM slave bus for access, each of which is 512 bytes long, with a total of 4 kB per ring. Each ring space starts immediately after the preceding ring. The allocation per ring is as in Table 10-409.
Offset | Operation | Supported Ring Modes |
---|---|---|
0x0 - 0x1FF | Reads pop from head. Writes push to head. | Read supported in all modes, write supported in all modes except Ring mode |
0x200 - 0x3FF | Writes push to tail. Reads pop from tail. | Write supported in all modes, read supported in all modes except Ring mode |
0x400 - 0x5FF | Reads peek from head. Writes ignored. | All modes except for Ring mode. |
0x600 - 0x7FF | Reserved | Peeks from tail are not supported in this device |
0x800 - 0xFFF | Reserved | Reserved |
Within each 512-byte (0x200) space, the message data is right justified so that the last byte is always the 511-th byte. The element size of the ring defines which words are valid. The word just before the first valid message word is the credentials field. Access must not be made before the credentials register .