VXI and VME

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Need help configuring a VME card in a VXI chassis

Can anyone tell me what I'm doing wrong? Or better yet, refer me to
somewhere I can learn for myself what I'm doing wrong (and will
undoubtedly do wrong in days to come ... )?

I have a VME card in a VME->VXI adapter. The card has a switch that is
set for "Base Address Select" = 0x0D (and the manual indicates that this
constitutes lines A31-A24).

Using T&M Explorer, I have added this device and mapped it to A32
address space 0x0D00_0000 to 0x0DFF_FFFF. (The other VME card is mapped
to A32 address space 0x2000_0000 - 0x2000-FFFF and one of the VXI cards
is mapped to A32 address space 0x4000_0000 - 0x41FF_FFFF.)

We have several other VXI cards (and one VME card) in our chassis. When
this new card is not
in the chassis, T&M Explorer reports that resman
has no problem with any of the other cards. When the new card is in the
chassis, T&M Explorer reports that resman has no problem with the other
VME card but shows red x's over some of the VXI cards and fails to see
another of the VXI cards.

If I then use NI-SPY to monitor traffic and use VISAIC to open a session
to the new VME card, NI-SPY reports failure on a call to viMemAlloc().
When I then remove the new VME card from the chassis (but leave it
configured in T&M Explorer) I can again use NI-SPY and VISAIC and get
results exactly as above.


Thanks in advance for any help or suggestions ...



B
--
ande at san dot rr dot com
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B-

Sorry for not seeing this question sooner. I suspect the answer is that the VME card is intercepting I/O to A16 space, which the VXI resource manager uses for configuration. You could probably verify this by opening the VXI0::MEMACC session in VISAIC and doing I/O to 0xC000-0xFFFF. Each VXI device has configuration space at 0xC000+0x40*LA, where LA is its logical address. If you are not able to communicate at the expected LA's, it may be because the VME device is responding instead. It might take a few experiments with VISAIC and Spy to fully characterize this behavior. If that is what is happening, you should probably double-check the documentation for your VME device to determine what A16 space it uses.

-Scot
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