Bootstrap loader
ST10F271Z1
6.3
6.3.1
6.3.2
6.3.3
Alternate and selective boot mode (ABM and SBM)
Activation of the ABM and SBM
Alternate boot is activated with the combination ‘01’ on Port0L[5..4] at the rising edge of
RSTIN.
User mode signature integrity check
The behavior of the selective boot mode is based on the computing of a signature between
the content of 2 memory locations and a comparison with a reference signature. This
requires that users who use selective boot have reserved and programmed the Flash
memory locations.
Selective boot mode
When the user signature is not correct, instead of executing the standard bootstrap loader
(triggered by P0L.4 low at reset), additional check is made.
Depending on the value at the user key location, following behavior will occur:
● A jump is performed to the standard bootstrap loader
● Only UART is enabled for bootstraping
● Only CAN1 is enabled for bootstraping
● The device enters an infinite loop.
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