CAN bus wiring question.

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I have a PCI computer card that has the following pinouts for CAN
communications.

CAN_L
CAN_H
SHIELD
V+
V-

Its a modicon type connector.  I know what the CAN_L and CAN_H is for,
however I have no clue where to hook the other three SHIELD, V+, V- to
on my circuit.

I was told the V+, V- is for external power, but I disabled it through
a jumper.  However I am wondering if I have to tie it to something.
If so what would it be?  Any idea?

PS:  The card is a National Instruments PCI-CAN card (from 1997)

Re: CAN bus wiring question.
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Connect the SHIELD pin to the shield around the CAN_L/CAN_H
twisted-pair.

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Probably not.

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Grant Edwards                   grante             Yow!  Th' MIND is the Pizza
                                  at               Palace of th' SOUL
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Re: CAN bus wiring question.

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Don't know about the expensive National board, but assume it doesn't need
the V+ and V-. These are optional power pins to power up the transceiver
and opto couplers. Most Interfaces are powering these parts from the other
side, from the PC logic.
And your Shield pin guess what it is for - for shielding your twisted
signale lines CAN_H and CAN_L.
You should have a look at: http://www.can-wiki.info/DeviceNetCable
  
Regards
 Heinz
--

with best regards / mit freundlichen Grüßen

   Heinz-Jürgen Oertel
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Re: CAN bus wiring question.

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The only use of the V+ and V- pins is to provide suitable voltages for
the "fail safe" termination, i.e. pulling the lines to the recessive
state, when no device is driving the bus to a dominant state.

Paul


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