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3.2.9
Security
TMS320F2808, TMS320F2806
TMS320F2801, UCD9501
Digital Signal Processors
SPRS230F–OCTOBER 2003–REVISED SEPTEMBER 2005
The 280x devices support high levels of security to protect the user firmware from being reverse
engineered. The security features a 128-bit password (hardcoded for 16 wait states), which the user
programs into the flash. One code security module (CSM) is used to protect the flash/OTP and the L0/L1
SARAM blocks. The security feature prevents unauthorized users from examining the memory contents
via the JTAG port, executing code from external memory or trying to boot-load some undesirable software
that would export the secure memory contents. To enable access to the secure blocks, the user must
write the correct 128-bit "KEY" value, which matches the value stored in the password locations within the
Flash.
NOTE
For code security operation, all addresses between 0x3F7F80 and 0x3F7FF5 cannot be
used as program code or data, but must be programmed to 0x0000 when the Code
Security Password is programmed. If security is not a concern, addresses 0x3F7F80
through 0x3F7FEF may be used for code or data. Addresses 0x3F7FF0 – 0x3F7FF5 are
reserved for data variables and should not contain program code.
The 128-bit password (at 0x3F 7FF8 - 0x3F 7FFF) must not be programmed to zeros.
Doing so would permanently lock the device.
NOTE
Code Security Module Disclaimer
The Code Security Module ("CSM") included on this device was designed to password
protect the data stored in the associated memory (either ROM or Flash) and is warranted
by Texas Instruments (TI), in accordance with its standard terms and conditions, to
conform to TI's published specifications for the warranty period applicable for this device.
TI DOES NOT, HOWEVER, WARRANT OR REPRESENT THAT THE CSM CANNOT BE
COMPROMISED OR BREACHED OR THAT THE DATA STORED IN THE ASSOCIATED
MEMORY CANNOT BE ACCESSED THROUGH OTHER MEANS. MOREOVER, EX-
CEPT AS SET FORTH ABOVE, TI MAKES NO WARRANTIES OR REPRESENTATIONS
CONCERNING THE CSM OR OPERATION OF THIS DEVICE, INCLUDING ANY
IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR
PURPOSE.
IN NO EVENT SHALL TI BE LIABLE FOR ANY CONSEQUENTIAL, SPECIAL, IN-
DIRECT, INCIDENTAL, OR PUNITIVE DAMAGES, HOWEVER CAUSED, ARISING IN
ANY WAY OUT OF YOUR USE OF THE CSM OR THIS DEVICE, WHETHER OR NOT
TI HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. EXCLUDED
DAMAGES INCLUDE, BUT ARE NOT LIMITED TO LOSS OF DATA, LOSS OF
GOODWILL, LOSS OF USE OR INTERRUPTION OF BUSINESS OR OTHER ECON-
OMIC LOSS.
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Functional Overview