d0ceef20f4
This commit renames all registers in xtensa/specreg.h to by adding the prefix XT_REG_. This is done to avoid naming collisions with similar variable names. A new register file, viz., xt_specreg.h is created. The previous names are still available to use but have been deprecated. Closes https://github.com/espressif/esp-idf/issues/12723 Merges https://github.com/espressif/esp-idf/pull/16040
| Supported Targets | ESP32 | ESP32-S2 | ESP32-S3 |
|---|
NMI ISR Example
This example demonstrates how to allocate and use non-maskable interrupt (NMI) on Xtensa-based targets. The asm_funcs.S file contains the ISR that will be run on the core that installed the NMI. The callback should be fairly simple and must be entirely written in assembly.
Defining an NMI handler can be done by defining a routine named xt_nmi. That routine will be called via call0 instruction, as such, before returning from the ISR, the return address register, a0, must be restored thanks to the instruction:
rsr a0, EXCSAVE + XCHAL_NMILEVEL
How to use example
Hardware Required
Example can run on any Xtensa-based ESP32 development board. Since the example uses GPIO19 as a bi-directional pin, make sure not to connect it to anything.
Configure the project
No particular configuration is required to run this example, the default one is suitable.
Build and Flash
idf.py build flash monitor
(To exit the serial monitor, type Ctrl-].)
See the Getting Started Guide for full steps to configure and use ESP-IDF to build projects.
Example output
example: Start
example: Success