Specifications

Double Buffer Mode Principle •• 71
6
Double Buffer Mode Principle
The data buffer for double-buffered DMA DI operation is a
circular buffer logically. It logically divided into two equal halves.
The double-buffered DI begins when device starts writing data
into the first half of the circular buffer (Figure 6-1a). After device
begins writing to the second half of the circular buffer, you can
copy the data from the first half into the transfer buffer (Figure 6-
1b). You now can process the data in the transfer buffer
according to application needs. After the board has filled the
second half of the circular buffer, the board returns to the first
half buffer and overwrites the old data. You now can copy the
second half of the circular buffer to the transfer buffer (Figure 6-
1c). The data in the transfer buffer is again available for process.
The process can be repeated endlessly to provide a continuous
stream of data to your application (Figure 6-1d).