Question on IRQ assert and Acknowledge

[Bhat_Maanay_Rice]

In the GPIC reference design labVIEW 2014 (GPIC 3-Phase-to-AC Inverter control.vi) I have some questions regarding interrupts 10 and 11.

In the RT vi, it appears that the program first waits on IRQ -10 then writes to DMA rate(Ticks), then acknowledge IRQ-10, then moves on to wait on IRQ-11 then I can't locate where IRQ-11 is acknowledged.

But in the FPGA vi (from what I understand) the code waits on the RT target to acknowledge IRQ-10 before writing to DMA rate (Ticks) and again waits on Acknowledge of IRQ-11 before writing to samples per channels and other variables.

So can someone please walk me through what's going on between the FPGA and the RT tragets regarding the IRQ wait and acknowledge and the data read and write please?

[Bhat_Maanay_Rice]

My main question would be How does the read/write node that appears between IRQ-10 assert and acknowledge work when the fpga can only write to that variable after IRQ-10 has been acknowledged?

[smithd]

I'm not sure I totally understand but I'll try to clarify.

The read/write control is setting a value in a register on the FPGA. So the sequence is FPGA hits an IRQ and waits for response, then RT sets the value of that hardware register, then acks the irq. This allows the FPGA to continue executing at which point it reads that register "DMA rate" and IRQs again.

IRQ 11 is ack'd inside of the start method for the waveform reference library (RIOStart.vi)

[Bhat_Maanay_Rice]

Thanks smithd.... Great help!