Problem with Aptina AR0331 sensor(HiSPi mode) on TI8127 IPNC platform

Hi Sean,

Does Vsync measure 60Hz, and after several minutes is there an unexpected transition?  Or does Vsync just go to 0V entirely?  Are you using the 12-bit mode of AR0331?  The DM8127 is designed to work with the AR0331 and LVDS324.

Are you using the Engineering Converter Board to interface between the sensor board and DM8127?  If so, how long are the 2 FFC's?  (in this setup, short 3cm FFC's should be used).

Thanks,
RE

It would also be helpful if you could capture the waveform of the unexpected Vsync signal.

Thanks,
RE

Hi RE,

 1. I don't measure 60Hz of Vsync, Vsync just go to 0V entirely.

 2. I confige AR0331 as HiSpi 4-lane, 12-bit mode.

 3. The FFC is shorter than 3 cm.

Do you think the 8127 pin configuration is OK?  Only the Vsync is abnormal , the others are normal. It's very strange.

I use the IPNC RDK v3.00 firmware.

Thanks,

Sean

Sean, can you view the RS-232 log output from the DM8127?  Does it say anything when Vsync goes to 0V?  The log can help us determine what is happening.

Thanks,
RE

One thing I've seen before is noise on the I2C_SCL signal, since there's coupling from the adjacent D0 signal.  It's possible that this could be your problem (but the log would tell us better).  A simple fix to that issue is to add a 500-700pF cap from I2C_SCL to GND.

Thanks,
RE

Sean,

Are you designing your own sensor board using the LVDS chip?

When you saw VSYNC is abnormal, does it mean that the waveform shape is also random and looks noisy? I saw such a problem on another sensor board which was due to the power supply issue. Can you try connecting the sensor board to a independent power supply?

Regards

Rajat

Hi Sean, I wanted to make sure you were able to resolve your problem.

Thanks,
RE

Hi RE:

Unfortunately, it still doesn't work!

I also found that M3VPSS main loop will shut down ??

I tried to print message in the M3SVPSS main loop function to check it's status.

After a few minutes, the message didn't print out anymore.

We try to connect our main board to Aptina 9P003 sesnor board and use the ipnc code, so that we cound make sure our main board is OK!

Thanks,

Sean 

Sean, I understand that the M3VPSS stops printing once Vsync goes to 0V.  Is there any message that it prints right when it stops?  For example, the noise issue that I've seen before causes it to print "I2C: Arbitration lost !!!"  If you see some particular message, that can help us pinpoint the problem.

Thanks,
RE

Hi RE:

Here is the RS232 log file,0434.8127_log.txt

I print the AR0331 and LVDS register settings,but I didn't see the message you mentioned

Thanks,

Sean