OTP programming

The OTP programs the same as FLASH except that it cannot be erased.

You can program it in-system using the FLASH API.

You should also be able to program it by defining a section within your program and setting constant data to that section.

In SECTIONS of the linker command file you could put:

myotp : > OTP     PAGE 0

Then in your program you can put:

#pragma DATA_SECTION(otpdata,"myotp");

const Uint16[4] = {0x1, 0x2, 0x3, 0x4};

The above will cause the program to allocate the 4 words to the section "myotp" which the linker will then place into OTP block.

Caution: check the linker map file to make sure you that the locations are what you want where you want. OTP begins at 0x3D7800 and ends at 0x3D7BFF.

When you load the program the OTP will be programmed along with the FLASH. (I haven't done this myself - I use in-system programming - but it should work). Just remember that once you program OTP locations with a zero bit you can never go back)

Depending on what you are doing you may find it better to program the OTP through a small program derived from the flash API examples.

If you are trying to program OTP_KEY and OTP_BMODE locations for the boot rom then you can modify the linker command file to create a block for each of these (they are the last two words of the OTP block) and then you can define them with a #pragma data section. This is similar to the way "BEGIN" is defined.

Hope this helps.