Silicon Labs EFM32TG11B
The Silicon Labs EFM32TG11B series belongs to the EFM32 device family from Silicon Labs.
Securing the device
In order to secure the device, it is necessary to program the desired protection bits into the "Lock Bits Page". This part of the flash is known by the J-Link DLL and can be memory mapped accessed / programmed as usual flash memory.
In the table below, you can find an short overview over the content of the Lock Bits flash page. Each item is one word (4 byte) in size. The page is memory-mapped starting at address 0x0FE04000.
For more details regarding the function of each bit, please refer to the corresponding reference manual (Page 138 - 6.3.2 Lock Bits (LB) Page Description) from SiLabs.
|Name||Description||Offset in byte||Absolute address|
|PLW[N]||Main block page lock||0 - 0x1E4||0x0FE04000 - 0x0FE041E4|
|CLW0||Bootloader enable and pin reset soft bit||0x1E8||0x0FE041E8|
|ALW||Authentication Access Port lock||0x1F0||0x0FE041F0|
|MLW||Mass erase lock||0x1F4||0x0FE041F4|
|ULW||User data page lock||0x1F8||0x0FE041F8|
|DLW||Debug lock word||0x1FC||0x0FE041FC|
In this example we will program the Lock bits via J-Flash.
- EFM32TG11B device
- J-Link with a valid J-Flash license included
- J-Link Software installed
- Start J-Flash and create a new project
- Select the correct device
- Read back the "Lock Bits Page": Target -> Manual Programming -> Read back -> Range... and set the correct range (0xFE04000 to 0xFE041FC).
- Clear / set the bits you want to disable / enable and hit F7 to program.