Texas Instruments TMS320F2837 D Series Workshop Guide And Lab Manual

Dual Code Security Module (DCSM)
TMS320F2837xD Microcontroller Workshop - System Design 10 - 15
CSM Caveats
 Never program all the PWL’s as 0x0000
 Doing so will permanently lock the zone
 Programming the PSWDLOCK field with any
other value than “1111” (0xF) will lock and
secure the password locations
 Remember that code running in unsecured
RAM cannot access data in secured memory
 Don’t link the stack to secured RAM if you have
any code that runs from unsecured RAM
 Do not embed the passwords in your code!
 Generally, the CSM is unsecured only for debug
 Code Composer Studio can unsecure the zone
CSM Password Match Flow
Zone secure
after reset or
runtime
Dummy reads of CSM
PWL of secure zone (that
needs to be unsecure)
Start
Zone
permanently
locked
Zone
Unsecure
Write CSM password
of that zone into
CSMKEYx registers
Correct
password?
Is PWL =
all Fs?
Is PWL =
all 0s?
Yes
Yes
Yes
No
No
No

Texas Instruments TMS320F2837 D Series Specifications

General

Brand	Texas Instruments
Model	TMS320F2837 D Series
Category	Microcontrollers
Language	English