ST10F276-4TR3 View Datasheet(PDF) - STMicroelectronics

Part Name

Description

Manufacturer

ST10F276-4TR3

16-bit MCU with MAC unit 832 Kbyte Flash memory and 68 Kbyte RAM

STMicroelectronics 

Bootstrap loader

5

Bootstrap loader

ST10F276E

ST10F276E implements innovative boot capabilities in order to

● support a user defined bootstrap (see Alternate bootstrap loader);

● support bootstrap via UART or bootstrap via CAN for the standard bootstrap.

5.1

Selection among user-code, standard or alternate bootstrap

The selection among user-code, standard bootstrap or alternate bootstrap is made by

special combinations on Port0L[5...4] during the time the reset configuration is latched from

Port0.

The alternate boot mode is triggered with a special combination set on Port0L[5...4]. Those

signals, as other configuration signals, are latched on the rising edge of RSTIN pin.

The alternate boot function is divided in two functional parts (which are independent from

each other):

Part 1: Selection of reset sequence according to the Port0 configuration: User mode and

alternate mode signatures

● Decoding of reset configuration (P0L.5 = 1, P0L.4 = 1) selects the normal mode and

the user Flash to be mapped from address 00’0000h.

● Decoding of reset configuration (P0L.5 = 1, P0L.4 = 0) selects ST10 standard bootstrap

mode (Test-Flash is active and overlaps user Flash for code fetches from address

00'0000h; user Flash is active and available for read and program).

● Decoding of reset configuration (P0L.5 = 0, P0L.4 = 1) activates new verifications to

select which bootstrap software to execute:

– if the user mode signature in the user Flash is programmed correctly, then a

software reset sequence is selected and the user code is executed;

– if the user mode signature is not programmed correctly but the alternate mode

signature in the user Flash is programmed correctly, then the alternate boot mode

is selected;

– if both the user and the alternate mode signatures are not programmed correctly in

the user Flash, then the user key location is read again. Its value will determine

the behavior of the selected bootstrap loader.

Part 2: Running of user selected reset sequence

● Standard bootstrap loader: Jump to a predefined memory location in Test-Flash

(controlled by ST)

● Alternate boot mode: Jump to address 09’0000h

● Selective bootstrap loader: Jump to a predefined location in Test-Flash (controlled by

ST) and check which communication channel is selected

● User code: Make a software reset and jump to 00’0000h

46/235

Doc ID 12303 Rev 3

Share Link: