[mach]

Neeraj,

Is there a special command sequence that I can use to see if the bootloader selects the SD card’s boot mode?

I have probed the cmd and clk lines and recorded the communication between the bootloader and the sd card with an logic analyzer. See the attached text file.

When evaluating the recorded data, I noticed that the bootloader repeatedly sends command 41 to the SD card during the initialization phase. However, this seems to go wrong. Because the same error bits are always set in the response from the SD card (COM_CRC_ERROR, ILLEGAL_COMMAND, DEVICE_ECC_FAILED, CC_ERROR, ERROR). However, it is not clear to me what the cause of the error messages is. Is it the bootloader, the hardware, or both, or can I ignore the error messages? Do you have any ideas?

Best,
Marco

Attachments:

1. logic_analyzer.txt

[mach]

Hi Neeraj,
the EMU0/1 pins are not pulled up as described in  Errata 1.0.36.

The board powers up. “Ccc’s” are output via the serial debug console after switching on the board.

In the OSD3358-SM-RED design TRSTN is grounded. In our design  TRSTN  is unconnected.
Should  TRSTN always be grounded even if it is not connected to the debug probe?
Or is it necessary to connect the (grounded) TRSTN pin to the debug probe?

Additionally in the OSD3358-SM-RED design TCKRTN is connected to TCK.
Is this mandatory? What exactly does this do?

Best,
Marco

Attachments:

1. 

   jtag_circuit.png
   

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