SPRUJ53B April 2024 – September 2024 TMS320F28P550SJ , TMS320F28P559SJ-Q1
In addition to the CSM, the emulation code security logic (ECSL) has been implemented using a 64-bit password (part of existing CSM password) for each zone to prevent unauthorized users from stepping through secure code. A halt in secure code while the emulator is connected trips the ECSL and breaks the emulation connection. To allow emulation of secure code, while maintaining the CSM protection against secure memory reads, write the correct 64-bit password into the CSMKEY (0/1) registers, which matches the password value stored in the USER OTP of that zone. This disables the ECSL for the specific zone.
When initially debugging a device with the password locations in OTP programmed (secured), the emulator takes some time to take control of the CPU. During this time, the CPU starts running and can execute an instruction that performs an access to a protected ECSL area and if the CPU is halted when the program counter (PC) is pointing to a secure location, the ECSL trips and causes the emulator connection to be broken.
The answer to this problem is to use the Wait Boot Mode boot option. In this mode, the CPU is in a loop and does not jump to the user application code. Using this BOOTMODE, you can connect to CCS and debug the code.