sdilucca

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Feb 10, 2009
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I have a PCI card that operates independent of the backplane. What I mean by that is that the power is drawn directly from the power supply and the communication takes place via a serial port. This card will literally work without being inserted into a PCI slot. However, I do insert it into the PCI slot because it needs to be physically supported. The "slot section" of the card is electrically isolated from the rest of the card and the slot terminals are also isolated from each other. Here is my dilemma... I can not just take the card out of the slot while the computer is on because it results in a crash. This makes no sense to me. How is the computer even aware that a card is present if no electrical circuits are being closed. To me there is no difference between placing this PCI card or a piece of wood in that slot. Hope I made myself clear. Anyone have any ideas why I can't hot swap?
 

sdilucca

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Feb 10, 2009
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It is a custom made card that calculates and transmits car axle count via RS232. There are sensors embedded in the roadbed which transmit on/off signals to this card via an RJ45. The reason I would want to remove it is for replacement. But I do not want to interrupt my operation just to replace a card. This card is actually connected to a backplane. Let me know if you need more detailed info about the backplane. I don't understand why the computer crashes if the card components are electrically isolated from the PCI slot.
 
The OS is probably detecting what devices is plugged into the PCI slot in realtime, and when you pull it out, since the address space that device took up can no longer be referenced, it brings down the system.
 

MaDMagik

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Oct 12, 2008
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Yeah, but since its isolated and only uses the pci port as a "holder" just pulling the card out shouldnt result in a crash , it should if you disconnect the serial port or power from it, as its not hot-swappable interface.