
The bootstrap loader
UM0404
DocID13284 Rev 2
when ST10F276 is reset with P0L.4 low. After loading a preselected number of bytes,
ST10F276 begins executing the downloaded program.
3.
The First level user code run on ST10F276. Typically, this first level user code is
another loader that is used to download the application software into the ST10F276.
4.
The loaded application software is now running.
Figure 125. Booting steps for ST10F276
15.2.4
Hardware to activate BSL
The hardware that activates the BSL during reset may be a simple pull-down resistor on
P0L.4 for systems that use this feature upon every hardware reset. You may want to use a
switchable solution (via jumper or an external signal) for systems that only temporarily use
the bootstrap loader.
Note:
CAN alternate function on Port4 lines is not activated if the user has selected eight address
segments (Port4 pins have three functions: I/O port, address-segment, CAN). Boot via CAN
requires that four address segments or less are selected.
External device
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External device
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External device
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External device
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Run Bootstrap Code
Run 1st level Code
Run Application Code
Step1
Step2
Step3
Step4
Download
1st level user code
Download
Application
Entering bootstrap
Loading 1st level user code
Loading the application
and exiting BSL
ST10F2
ST10F2
ST10F2
ST10F2
from Test-Flash
from DPRAM @FA40h