STM8S105C4 datasheet(15/121 Pages) STMICROELECTRONICS

15 / 121 page

DocID14771 Rev 15

15/121

STM8S105x4/6

Product overview

The size of the UBC is programmable through the UBC option byte, in increments of 1 page

(512 byte) by programming the UBC option byte in ICP mode.

This divides the program memory into two areas:



Main program memory: up to 32 Kbyte minus UBC



User-specific boot code (UBC): Configurable up to 32 Kbyte

The UBC area remains write-protected during in-application programming. This means that

the MASS keys do not unlock the UBC area. It protects the memory used to store the boot

program, specific code libraries, reset and interrupt vectors, the reset routine and usually

the IAP and communication routines.

Figure 2. Flash memory organization

Read-out protection (ROP)

The read-out protection blocks reading and writing the Flash program memory and data

EEPROM memory in ICP mode (and debug mode). Once the read-out protection is

activated, any attempt to toggle its status triggers a global erase of the program and data

memory. Even if no protection can be considered as totally unbreakable, the feature

provides a very high level of protection for a general purpose microcontroller.

STM8S105C4 Datasheet(PDF) 15 Page - STMicroelectronics