The TI E2E™ design support forums will undergo maintenance from Sept. 28 to Oct. 2. If you need design support during this time, contact your TI representative or open a new support request with our customer support center.

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

AM3356: Enable debug port security and serial port locking in AM335x series

Part Number: AM3356

Hello, 

Can anyone help me in knowing how can I lock JTAG port (debug port) and secure my serial interfaces in AM335x series chipset. 

Thank you. 

  • Hello,
    1. On "lock JTAG port (debug port)"
    Here's recent e2e discussion on the topic
    e2e.ti.com/.../1084320
    2. Can you elaborate "secure my serial interfaces" use case in more details?
    Best,
    -Hong

  • Hi Hong, 

    Thanks for the reply. 

    Please spare me but I am not a developer so I could not understand how to lock JTAG. 

    Also can you please explain this

    'The CONTROL_SEC_TAP register @0x44E1:0180 is not typically used on GP device, but the register is accessible on GP device'. I can not see CONTROL_SEC_TAP register in the datasheet or technical manual. Though I can find this register in AM35x technical manual. Link is given here https://www.ti.com/cn/lit/ug/sprugr0c/sprugr0c.pdf

    How can I do it for AM335x series? 

    Also I want to prohibit hacker from reading and writing my serial interfaces like UART, I2C, SPI. Any solution to do that?

    Thanks for your help. 

  • Hello,

    'The CONTROL_SEC_TAP register @0x44E1:0180 is not typically used on GP device, but the register is accessible on GP device'. I can not see CONTROL_SEC_TAP register in the datasheet or technical manual.

    Let me clarify
    - The CONTROL_SEC_TAP register @0x44E1:0180 is not typically used on GP device, so it is not listed in AM335x TRM. but the register is accessible on GP device.

    How can I do it for AM335x series? 

    Please refer to the referenced e2e post on SW options locking JTAG debug port in SW, i.e. bootloader code.

    Also I want to prohibit hacker from reading and writing my serial interfaces like UART, I2C, SPI. Any solution to do that?

    One option could be not activating peripheral (UART, I2C, SPI...) clocks in SW.
    Best,
    -Hong