Proper use of camera connector in OMAP-L138 LCDK

Nuntipat narkthong

Other Parts Discussed in Thread: TXB0108, TVP5147

I'm trying to connect my custom made camera board to the camera connector of the LCDK board. However I observed from the schematic that port CVIDEO_DIN0-7 is shared with the digital video decoder TVP5147. How can I disable this chip without board modification? What is the purpose of r pull-up (R244 - R251)? Finally with R244 - R251 populate will the pull up resistor confuse the logic converter I use (TXB0108)? I need to use it because the LCDK board use 3.3v I/O but my camera module use 1.8v I/O.

Regards,

Palm

over 10 years ago

0 Senthilkumar Srinivasan over 10 years ago

TI__Mastermind 43660 points

Hello Nuntipat,

Welcome to TI E2E Forum.

The camera module can be interfaced to the J16 connector of LCDK without doing any change in the hardware. You can use either composite in or camera module at a time.

The TXB0108 that you are using in your design converts 1.8V logic to 3.3V logic. I don't think the pull up resistors to 3.3V make conflict over the logic converter.

Regards,

Senthil

0 Nuntipat narkthong over 10 years ago in reply to Senthilkumar Srinivasan

Prodigy 130 points

That sound good. From what I understand, the digital video converter (TVP5147) is able to sense when the composite cable is connected right. I'm just not quite sure how the chip know that the cable is connect and disable it's output to avoid logic contention.

Regards,

Palm

0 Senthilkumar Srinivasan over 10 years ago in reply to Nuntipat narkthong

TI__Mastermind 43660 points

Hello Palm,

When the video decoder sees the input signal from composite connector, then only it decodes the input and send the data to the VPIF controller. If you are using camera module and not composite input, the video decoder does not have any effect.

Regards,

Senthil

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Proper use of camera connector in OMAP-L138 LCDK