STM8 Debugger
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Breakpoints
Software breakpoints
The Microchip STM8 architecture does not support software breakpoints.
On-chip breakpoints for instructions
The STM8 MCUs support a total of two on-chip breakpoint registers which can be used as program
breakpoints to stop and debug the program which executes always in the Flash.
On-chip breakpoints for data
Data breakpoints are used to analyze the read and write accesses to global variables. The data breakpoints
can be triggered with respect to the data address or access type, i.e. read, write or both, or the data value.
The two instruction breakpoints of STM8 MCUs can be used as data breakpoints
In case of an on-chip data breakpoint, every load and store instruction is checked with respect to the
breakpoint address, access type and the value. The data breakpoints are especially useful to find out when
a global variable is written with a certain value. It is not possible to implement a similar breakpoint in software
without affecting the real-time behavior of the system. Since the load and store instructions work on RAM,
data breakpoints always point to addresses on RAM.