kopia lustrzana https://github.com/espressif/esp-idf
61 wiersze
2.7 KiB
Markdown
61 wiersze
2.7 KiB
Markdown
| Supported Targets | ESP32 | ESP32-S3 |
|
|
| ----------------- | ----- | -------- |
|
|
|
|
# IPC ISR Example
|
|
|
|
This example demonstrates how to use the IPC ISR feature (which allows an IPC to run in the context of a High Priority Interrupt). The level of the IPC ISR interrupt depends on the `CONFIG_ESP_SYSTEM_CHECK_INT_LEVEL` option. The IPC ISR feature can be useful in cases where users need to quickly get the state of the other CPU (consult the [IPC documentation](https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-reference/system/ipc.html)). The `asm_funcs.S` file contains the callback that will be run on the other core. The callback should be fairly simple and must be entirely in assembly.
|
|
|
|
The first assembly callback `get_ps_other_cpu()` demonstrates a callback that simply returns the `PS` register of other core.
|
|
|
|
The second assembly callback `extended_ipc_isr_asm()` demonstrates a more complex callback that uses a buffer (provided as the callback's argument) to save some registers and return multiple values from the callback. The callback's `void *arg` points to a buffer containing the following:
|
|
- `uint32_t regs[];` that gives the callback an area to save some of the CPUs registers. Saving the registers gives the callback more scratch registers to use.
|
|
- `uint32_t in[];` that gives the callback multiple input arguments
|
|
- `uint32_t out[];` that gives the callback multiple output arguments
|
|
|
|
The `extended_ipc_isr_asm()` callback will simply save/restore registers to/from `regs[]`, then use the arguments passed by `in[]` to do some work, then write the results to `out[]`.
|
|
|
|
## How to use example
|
|
|
|
### Hardware Required
|
|
|
|
Example should be able to run on any commonly available ESP32 development board. The chip should have two cores.
|
|
|
|
### Configure the project
|
|
|
|
- `CONFIG_FREERTOS_UNICORE` - disabled,
|
|
- `CONFIG_ESP_IPC_ISR_ENABLE` - enabled.
|
|
|
|
```
|
|
idf.py menuconfig
|
|
```
|
|
|
|
### Build and Flash
|
|
|
|
```
|
|
idf.py build flash monitor
|
|
```
|
|
|
|
(To exit the serial monitor, type ``Ctrl-]``.)
|
|
|
|
See the [Getting Started Guide](https://docs.espressif.com/projects/esp-idf/en/latest/get-started/index.html) for full steps to configure and use ESP-IDF to build projects.
|
|
|
|
|
|
## Example output
|
|
|
|
```
|
|
I (304) example: Start
|
|
I (304) example: call get_ps_other_cpu
|
|
I (314) example: PS_INTLEVEL = 0x5
|
|
I (314) example: PS_EXCM = 0x0
|
|
I (324) example: PS_UM = 0x1
|
|
I (324) example: call extended_ipc_isr_asm
|
|
I (324) example: in[0] = 0x1
|
|
I (334) example: in[1] = 0x2
|
|
I (334) example: in[2] = 0x3
|
|
I (334) example: out[0] = (in[0] | in[1] | in[2]) = 0x3
|
|
I (344) example: out[1] = (in[0] & in[1] & in[2]) = 0x6
|
|
I (354) example: out[2] = in[2] = 0x3
|
|
I (354) example: out[3] = PS of other cpu = 0x25
|
|
I (364) example: End
|
|
```
|