SPRUIZ1B July 2023 – August 2024 TMS320F28P650DH , TMS320F28P650DK , TMS320F28P650SH , TMS320F28P650SK , TMS320F28P659DH-Q1 , TMS320F28P659DK-Q1 , TMS320F28P659SH-Q1
RAMOPEN feature on this device enables a user to unsecure all of the secure RAM blocks without unlocking the zone security. Afterward, the RAMs can be converted back into secure RAMs without issuing reset to device. However, the previous contents of the secure RAM are not maintained.
This is a useful feature for Flash programming tools (for example, CCS Flash plugin, serial Flash programmer, and so on), which need to download Flash APIs and data on RAMs to carry out the Flash program/erase operations to unsecure Flash regions. Since debugger and boot loader writes are considered unsecure, the writes require either unsecure RAM or unlocked secure RAM to download the APIs and data to. However, the user can not always have the password required to unlock one or both of the security zones. This can be particularly problematic in a device with limited RAM where the majority of the RAM used during application runtime is designated as secure RAM.
The RAMOPEN feature allows the Flash programming tools to temporarily convert the secured RAM blocks into unsecured RAM blocks to load the API/Data and after Flash program/erase operation is completed, turn them back into secured RAM blocks.
The feature works as: