Dear Support,
Ive a developed a Board with a TMS570LS3137CZWT MCU and Connected to a XDS100v2 JTAG Emulator. Now I need to apply the 128 Bit Security Key (in the OTP Area) to prevent readout of the Firmware (Debugging is not neccassary). I use uniflash v3.1.
Q:
+ What are the steps to set the OTP Read Key?
+ Can the Boards be reflashed with a new Firmware afterwards?
regards,
Lorenz
To secure the TMS570LS3137CZWT using UniFlash, first you create an object file that contains the 128-bit code you want at location 0xF0000000. The default (unlocked) value at that location is:
0xEFFDFFFF, 0xFFFFFFFF, 0xFFFDFFFE, 0xFFEFFFFF.
The new code can be anything that turns '1' bits to '0' bits. If you choose the value of all 0's, the device will be permanently locked. Any other valid value will lock the device, but it can be unlocked if you know which bits were changed. The current tools from TI, CCS and UniFlash, do not support unlocking a locked device even if you know which bits were changed.
Next you program that object file into the device using UniFlash with "Enable Programming to OTP Memory" option selected on the "Flash Settings" page:
You can verify the device after programming, or even connect CCS and see the updated AJSM value in a memory window until you reset the part. Once you reset the part, you will no longer be able to connect with CCS or UniFlash. Remember that turning off the power will always cause a reset.
