Expansion Bus I/O Port Operation
8-19
Expansion Bus
8.4.2.4
Flag Monitoring
To efficiently control bursts to and from the dedicated FIFO interfaces, the in-
terrupt signals EXT_INT4, EXT_INT5, EXT_INT6, and EXT_INT7 are used as
flags to control DMA transfers. The flag polarity used to start transfer can be
programmed in the DMA secondary control register. The CPU EXT_INT and
DMA EXT_INT polarity are controlled separately. For more details see the
DMA section.