SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
The synchronous buffering scheme allows each ping or pong buffer to contain a single frame or a multiple number of frames. For this reason, the synchronous buffer depth (BDi) must be defined in terms of an integer number (n), frames per sub-buffer (m) and bytes per frame (bpf) of data (that is, BDi = n × m × bpf - 1).
Table 26-1637 shows the format for a synchronous DMA descriptor table entry. For more details about the field descriptions see Table 26-1636. Each synchronous channel buffer can be up to 8k-bytes deep.
In synchronous transmit mode software should take care that the pong DDT is configured before ping DMA completion and ping DDT is configured before pong DMA completion. For more information about ping and pong DMA configuration see Table 26-1649 and Table 26-1650, respectively.
| Bit Offset | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 0 | CE | LE | PG | Reserved | ||||||||||||
| 16 | Reserved | |||||||||||||||
| 32 | RDY1 | DNE1 | ERR1 | BD1[12:0] | ||||||||||||
| 48 | RDY2 | DNE2 | ERR2 | BD2[12:0] | ||||||||||||
| 64 | BA1[15:0] | |||||||||||||||
| 80 | BA1[31:16] | |||||||||||||||
| 96 | BA2[15:0] | |||||||||||||||
| 112 | BA2[31:16] | |||||||||||||||