DMA ABU mode - Half-buffer interrupts

Started by joeblogss84 November 25, 2002
Hello all,

'5416 device.

Using ABU mode, is there any way of determining which half of the
buffer the DMA is currently writing (in other words which half of the
buffer was just filled and generated the half or full buffer

We can of course use a simple flip-flop variable, which is toggled in
the ISR, as a simple framer but if an interrupt is missed (for
whatever reason) this system falls apart. Why would we miss an
interrupt - who knows but it is not good to know of a failure
mechanism in code you release is it.

Can the DMA count registers be accessed in some fashion? I have
looked through the documentation but did not find anything on this.

Ian Wilson