36.5.3.7.2 Updating an Existing Packet from the User Interface

To update an existing packet from the User Interface, follow the steps below:

  1. Write the address of the header of the packet to update in OTPC_MR.ADDR.
  2. Start a read by setting OTPC_CR.READ and wait for the read completion indicated by OTPC_ISR.EOR.
  3. Update the data using the OTPC_AR and OTPC_DR registers. Only the 32-bit data set to 0 can be updated, the non-zero 32-bit data must be left unchanged
  4. Write 0x7167 in the OTPC_CR.KEY field and ‘1’ to OTPC_CR.PGM.

The end of the programming operation is indicated by OTPC_ISR.EOP='1' and/or OTPC_SR.PGM='0'.

If the updated packet is the User Hardware Configuration special packet, its new payload is ignored until the next reset. The OTPC_UHCxR registers will be updated after the reset or the refresh following programming.