SPRUJF2A March 2026 – March 2026 AM13E23019
Software can generate a software POR, a software BOOTRST, a software SYSRST with bootstrap loader (BSL) entry, or a software SYSRST by issuing the appropriate command to SYSCTL. To issue a reset, first select the desired reset level in the RESETLEVEL register in SYSCTL. Then set the GO bit in the RESETCMD register along with the KEY value.
| LEVEL | Action |
|---|---|
| 0x0 | Software-triggered SYSRST |
| 0x1 | Software-triggerd BOOTRST |
| 0x2 | Software-triggered SYSRST with BSL entry |
| 0x3 | Software-triggered POR |
| 0x4 | Software-triggered CPURST |
A CPU-only reset (CPURST) which does not reset the peripherals can also be triggered in software within the device CPU by setting the SYSRESETREQ bit in the AIRCR local CPU register. See the CPU Sub System chapter for more information.
The software-triggered BSL entry (RESETLEVEL 0x02) is a special case of the SYSRST which provides a mechanism for the application software to start the ROM bootstrap loader (BSL). Direct access to the bootloader code is disabled during normal software execution in RUN mode. When application software commands a software-triggered BSL entry (RESETLEVEL 0x02), a SYSRST is generated first, followed by execution of the boot configuration routine (for authentication), after which the BSL is started (if the device security policy has enabled the BSL execution).
Once the BSL has completed execution, a second SYSRST is issued and the BCR is executed. When the BCR completes, a final SYSRST is asserted to return control of the system back to the application software.
If the BSL is disabled by the user configuration, and a software-triggered BSL entry is invoked, the device issues a standard SYSRST instead and returns control of the system back to the application software.
Any system configuration which is not reset by a SYSRST is maintained through this entire process.