NI 6533 and BUS.

[longest]

Hello!

I try to use PCI6533 for control application:
Each 50 us cycle simultaneously send and receive vectors of 64..200 samples.

1. Why benchmark result for output less then input benchmark result?

2. Case 1: Burst transfer 32-bit mode, 10 MHz samples rate
Case 2: Burst transfer 16-bit mode, 20 MHz samples rate.
Is equivalent PCI bus load for case 1 and 2 ?
(the "MITE" chip packs two 16 bit samples to one 32 bit word for send
via PCI...?)

Have difference between 6534 and 6533 in this questions?

3.Looking at "Maximizing the Performance of the NI 6534 Digital I/O Device".
DMA Transfer Size
4-byte blocks for PCI6533
32-byte blocks for PCI6534
Is it means that DMA mode for PCI6533 non-effective (too many address
information in P
CI frame) for 8 samples
block transfers (FifoReadyLevel=3)?

Thanks.

[LA 75]

Hello,

1. It is less because the PCI-6534 uses an Onboard Scrab memory that enables you to transfer data to/from this memory at a guarantee rate. The PCI-6534 doesn't have this memory.

2. Yes, the PCI-bus load would be equivalent for both cases and the chip would be packing twice the number of samples for the 16-bit than the 32-bit samples.

3. DMA is only supported by PCI-6534, its not supported by PCI-6533.

Please let me know if you have any additional questions. Thanks!

LA