[ADV8005]SPI loop through is not possible

Hi,

  By default, the SPI ports are set in manual mode for the SPI which means the SPI pins are tristated (input). To make the SPI ports operational, the following register bits must be configured to automatic mode, So 0x1ACE register should configure as 0x00(Auto).

  Also refer figure88 for SPI loop back mode connection.

Thanks,

Poornima

Hi,

  By default, the SPI ports are set in manual mode for the SPI which means the SPI pins are tristated (input). To make the SPI ports operational, the following register bits must be configured to automatic mode, So 0x1ACE register should configure as 0x00(Auto).

  Also refer figure88 for SPI loop back mode connection.

Thanks,

Poornima

Hi,

Thank you for answering.
I tried with register setting 0x1ACE = 0x00, but no SCK was output.
Are there any other registers that need to be configured to enable SPI?
Also, is there an order to set the registers?
The hardware is directly connected to the MCU --- (SPI1) ADV8005 (SPI2) --- SPI flash, like the EVM.
Do any pins need pull-up or pull-down settings for SPI use?

I investigated further.
MISO2 and CS2 are output with SPI loop-through setting.
Only SCK2 is not output.
There is no doubt about the pin assignment.
SCK2 (A9)
MOSI2 (B9)
MISO2 (B10)
CS2 (A10)
There are no disconnections or short circuits in the wiring. I don't understand at all.

Thank you.

Hi,

   Please refer crosscheck your schematic here at https://ez.analog.com/video/w/documents/697/advantiv-eval-adv8003-smz-video-evaluation-board

   Also please note that For this SPI loop through system "MCU is responsible for any error protection for this mode".

Thanks,

Poornima

Hi,

I left the PDN pin on the ADV8005 open.
(The hardware manual wrote  "This pin must be connected.")
Is it possible that this causes the SPI clock to not be output?

Thank you.

Hi,

  As per hardware manual specification this PDN pin must be connected, Please refer below snap

Note:  PDN pin controls the power down for all blocks in ADV8005.
            Please refer section Power Supply Design and Sequencing in ADV8005 hardware manual at Page 290.

Thanks,

Poornima