EFM8SB1 Datasheet, PDF (11/55 Pages) Silicon Laboratories – The EFM8SB1 highlighted features are listed below

EFM8SB1 Data Sheet
System Overview
3.10 Bootloader
All devices come pre-programmed with a UART bootloader. This bootloader resides in the last page of flash and can be erased if it is
not needed.
The byte before the Lock Byte is the Bootloader Signature Byte. Setting this byte to a value of 0xA5 indicates the presence of the boot-
loader in the system. Any other value in this location indicates that the bootloader is not present in flash.
When a bootloader is present, the device will jump to the bootloader vector after any reset, allowing the bootloader to run. The boot-
loader then determines if the device should stay in bootload mode or jump to the reset vector located at 0x0000. When the bootloader
is not present, the device will jump to the reset vector of 0x0000 after any reset.
0xFFFF
Reserved
0x2000
0x1FFF
0x1FFE
0x1FFD
0x1E00
Lock Byte
Bootloader Signature Byte
Security Page
512 Bytes
Bootloader Vector
8 KB Flash
(16 x 512 Byte pages)
0x0000
Reset Vector
Figure 3.2. Flash Memory Map with Bootloader—8 kB Devices
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