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CAN module "stuck" in configuration mode!

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2moto
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2014/03/24 16:36:27 (permalink)
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CAN module "stuck" in configuration mode!

I am using a PIC32MX575 and am trying to get the CAN module to work. I have read the CAN reference module and have some familiarity with CAN-Bus. So, I created a simple function to write the various configuration registers, following the examples in the reference manual closely.
 
I request a mode change to configuration, and that happens (confirmed via opmode). I then write a bunch of registers, and request loopback mode change. Reading back the opmode, it remains in 4 (configuration). I've even commented everything out, with just the mode changes remaining.  Still refuses to come out of configuration mode.
 
I am using CAN1 module and there is a MCP2562 transceiver connected to the RX/TX lines. The transceiver is not connected to a CAN-Bus yet.
 
Anyone have any clues? From what I read, it should at least enter loopback mode...
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    tom_usenet
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    Re: CAN module "stuck" in configuration mode! 2014/03/29 18:52:43 (permalink)
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    This is a very frequently asked question. Search for "stuck in configuration mode" to find previous answers.
     
    Tom
     
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    2moto
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    Re: CAN module "stuck" in configuration mode! 2014/03/30 00:12:11 (permalink)
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    I did that before making the post, Tom, and none of the search results helped.
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    tom_usenet
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    Re: CAN module "stuck" in configuration mode! 2014/03/31 00:14:48 (permalink)
    +2 (2)
    > The transceiver is not connected to a CAN-Bus yet.
     
    That's one of the common causes of this problem. The CAN Bus has to be completely "idle" for the chip to transition out of configuration mode. Are the transceiver pins terminated at least, or are they completely disconnected?
     
    Is there anything in the setup of the rest of the chip that might mean you're not giving it a clock?
     
    Here's another one where the wrong pins on the chip were configured:
     
    http://www.microchip.com/forums/m674016.aspx
     
    Tom
     
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