How can I verify that the PCI-6534 is using all of its onboard memory?

[MikeH]

When using a PCI-6534 under Windows 98 with NI-DAQ 6.9, I need to transfer a small buffer (8126464 bytes) to the adapter, and get it into the onboard memory. The board is configured for 32 bits output, and I'm using handshake mode. DAQ_GET_DEVICE_INFO tells me that there is 33554432 bytes for each Group. DIG_Block_Check shows that 2031587 words (8126348 bytes) are remaining to transfer. Is that in the PC system memory or the PCI-6534 on board memory? How can I tell if it is safe to reuse the (PC side) buffer? Also, How big is the FIFO on the PCI-6534?

[ciro]

When you call DIG_Block_Out, NI-DAQ first downloads your data into the 6534 memory. Only after the download is done (which should happen at about 80 MB/s) it starts outputting data and DIG_Block_Out returns. So it is safe for you to reuse your PC memory buffer as soon as DIG_Block_Out returns.

This is assuming your entire buffer fits in memory. If it doesn't, NI-DAQ will download all the data that fits and start the transfer, and as more 6534 memory becomes available the DMA channel will fill it up.

The 6534 has a 16 sample FIFO and an additional 32 MB of memory for each handshaking group. So for 32-bit transfers you can fit 8 MSamples, for 16-bit transfers you can fit 16 MSamples (per group), and for 8-bit transfers you can fit 32 MSamples (per group) in the 6534
memory.