EFM32WG Datasheet, PDF (28/834 Pages) List of Unclassifed Manufacturers – The EFM32WG Wonder Gecko is the ideal choice for demanding 8-, 16-, and 32-bit energy sensitive applications.

Figure 6.2. Device Unlock
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Reset
Locked No access
150 us
Unlocked No access
Ext ended
unlocked
No access
Figure 6.3. AAP Expansion
SWDIO
SWCLK
AAP expand
Pr o g r a m
execution
AAP
Pr o g r a m
execution
AAP
Cort ex
47 us
Pr o g r a m
execution
Ext ended AAP
Cort ex
255 x 47 us
The device is unlocked by writing to the AAP_CMDKEY register and then setting the DEVICEERASE bit
of the AAP_CMD register via the debug interface. This erase operation erases the main block of flash,
all lock bits are reset and debug access through the AHB-AP is enabled. The operation takes 125 ms to
complete. Note that the SRAM contents will also be deleted during a device erase.
The debugger may read the status from the AAP_STATUS register. When the ERASEBUSY bit is set
low after DEVICEERASE of the AAP_CMD register is set, the debugger may set the SYSRESETREQ
bit in the AAP_CMD register. After reset, the debugger may resume a normal debug session through
the AHB-AP.
Note
If the debug pins are reconfigured for other I/O purposes than debug, a device erase may
no longer be executed. The pins are configured for debug in their reset state.
6.4.1 Device Erase During Reset
If the software disables the debug pins (making a device erase impossible), the erase command may
also be issued while pin reset is asserted. A device erase will then be performed as soon as reset is
deasserted.
2013-05-08 - Wonder Gecko Family - d0233_Rev0.50
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