Chief Delphi - Camera glitch / failure

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Camera glitch / failure

I am having a problem with the 2005 camera code and the 2006 controller. The camera will "glitch" randomly and never recover. I have had the thing run for 30 minutes with no problems, and yet sometimes it will give out in five seconds!

It is giving all the appearences of a receive failure, and resetting the RC is the only thing that can make it recover. I have tried 2 different camera boards, with and without the TTL converter (made a special cable for without!). I have tried software and hardware resetting the camera board, to no avail. (It resets the camera board, but the RC never seems to receive anything, including the power-on ACKs, after the failure).

Can anyone help me on this? It is frustrating me to no end. When I say random, I mean random! :ahh: :confused: :( :mad:

EDIT:
I wonder if this will clear up the problem? It looks as if maybe we are setting the RX overflow bit now and them (maybe due to a coincidental firing of a lot of interrupts in a short period of time), and this will halt the RX completely until the following code is called.

Kevin, could you please help me with this? I haven't worked directly with the PIC USARTs before. :)

Code:

if(RCSTA2bits.OERR)

  {

    RCSTA2bits.CREN = 0;                // Make sure the receive is still enabled!

    RCSTA2bits.CREN = 1;

    RXINTE2 = 1;

  }

Re: Camera glitch / failure

Quote:

Originally Posted by Eldarion

Code:

if(RCSTA2bits.OERR)

{

RCSTA2bits.CREN = 0;                // Make sure the receive is still enabled!

RCSTA2bits.CREN = 1;

RXINTE2 = 1;

}

Make sure the serial port receive interrupts are the first to get serviced in the low-priority ISR. If it is an overrun error, you can only fix it by resetting the serial port Rx circuit with this code:

Code:

 

// if the interrupt handler was disabled while data was being received,

// data may have backed-up in the receiver circuitry, causing an overrun

// condition. So let's check the OERR bit to see if this has happened

// and if it has, we'll need to reset the serial port receiver circuitry

// to get data flowing again.

if(RCSTA1bits.OERR)

{

// reset by turning off the receiver circuitry, then...

RCSTA1bits.CREN = 0;

 

// ...turn it back on

RCSTA1bits.CREN = 1;

 

// indicate that we've had an error

RX_1_Overrun_Errors++;

}

If you're using my serial port driver, this is automatically handled in the Rx ISRs. If you aren't using my code, you can place this code in the fast loop.

-Kevin

Re: Camera glitch / failure

OK, thanks. That worked just great! :)

It is maddening to waste a few days trying to fix an error that can be fixed by flipping one bit. :rolleyes: