15.1.3.2 % Efficiency
A typical Read transfer consists of:
- Total clks = CMD + ADDR + Dummy Byte(/s) + spi_clks between dummy byte tx to Read start + (reads spi_clks per trans × number of trans per CS# low) + (idle spi_clks between two reads × number of reads in CS# low - 1) + end of read to start of new read
- So, total spi_clks = 8 + 24 + 8 + 8 + (32 × 8) + (8 × 7) + 13 = 373
- Actual spi_clks in a transfer (CS# low) = 32 × 8 = 256
- Typical % efficiency = (256/373) × 100 = 68.63%
- A throughput of 19.5 MB/s (typically for a EDMA transfer). So the typical efficiency will be:
(19.5/30.5) × 100 = 64%
- 4% efficiency delta could be because of 20-MHz timer that is used to measure count for transfers.