ANX SDK Initialization and System Functions

anx/anx.h is the core header you include in every ANX application. It initializes the ANX OS integration layer — setting up the task scheduler, memory allocator, and peripheral clocks — and provides the system utilities your application needs from the very first line of app_main() all the way through to graceful shutdown and reboot.

`app_main()` Entry Point

Define void app_main(void) as the single entry point for your application. ANX OS calls this function automatically after the system initializes all hardware and loads config.json from the device filesystem. You do not need a main() function — the ANX OS boot sequence handles everything before app_main() is invoked, so all peripherals are ready the moment your code runs.

app_structure.c

#include "anx/anx.h"

void app_main(void) {
    // Called by ANX OS after boot
    // All peripherals are ready at this point
    ANX_LOGI("APP", "Application started");
    ANX_LOGI("APP", "Firmware: %s", anx_firmware_version());
    ANX_LOGI("APP", "SDK: %s", anx_sdk_version());
}

ANX OS will halt with a fatal error if app_main() is not defined in your application binary. Make sure it is present in exactly one translation unit.

System Information Functions

Use these functions to read device metadata at runtime. They are safe to call anywhere inside app_main() and are commonly used in startup log messages or OTA compatibility checks.

`anx_firmware_version()`

Returns a null-terminated string containing the firmware version currently running on the device (for example, "1.2.0").

return

const char *

A pointer to a static string holding the firmware version in MAJOR.MINOR.PATCH format. Do not free or modify this string.

`anx_sdk_version()`

Returns a null-terminated string containing the version of the ANX SDK your application was compiled against (for example, "1.2.0").

return

const char *

A pointer to a static string holding the SDK version in MAJOR.MINOR.PATCH format. Do not free or modify this string.

`anx_device_id()`

Returns a null-terminated string containing the unique device identifier derived from the module’s 48-bit MAC address (for example, "a1b2c3d4e5f6"). Use this value to uniquely identify a device in your backend or MQTT topic hierarchy.

return

const char *

A pointer to a static string holding the 12-character hexadecimal device ID. Do not free or modify this string.

Logging Functions

ANX OS provides four log-level macros that write formatted output to the serial console. Each macro accepts a short tag string (conventionally the subsystem name, like "APP" or "WIFI") so you can filter output from multiple components at a glance.

Macro	Level	Visibility
`ANX_LOGE(tag, fmt, ...)`	Error	Always shown
`ANX_LOGW(tag, fmt, ...)`	Warning	Always shown
`ANX_LOGI(tag, fmt, ...)`	Info	Shown at `info` log level and above
`ANX_LOGD(tag, fmt, ...)`	Debug	Shown only when `log_level` is set to `"debug"` in `config.json`

logging_example.c

#include "anx/anx.h"

void app_main(void) {
    ANX_LOGI("APP", "Device ID: %s", anx_device_id());
    ANX_LOGD("APP", "Debug details visible only in debug builds");
    ANX_LOGW("APP", "Low memory: %u bytes free", anx_free_heap());
    ANX_LOGE("APP", "Critical failure, rebooting");
    anx_reboot();
}

Keep tag strings short — four to six characters — so log lines stay readable at a glance in a serial monitor.

Delay and Timing Functions

`anx_delay_ms()`

Yields the CPU for the specified number of milliseconds, allowing other tasks in the ANX OS scheduler to run during the wait.

uint32_t

required

Number of milliseconds to delay. The actual delay may be slightly longer than requested due to scheduler tick resolution.

return

void

This function does not return a value.

`anx_delay_us()`

Busy-waits for the specified number of microseconds, blocking the CPU for the entire duration. Use this only when you need sub-millisecond precision that the scheduler cannot guarantee.

uint32_t

required

Number of microseconds to busy-wait. Avoid values larger than a few hundred microseconds in tasks that share CPU time with networking or file I/O.

return

void

This function does not return a value.

anx_delay_us() blocks the CPU for its entire duration. Calling it with large values in a networking-heavy application can cause Wi-Fi stack timeouts or dropped MQTT connections.

`anx_uptime_ms()`

Returns the number of milliseconds elapsed since the last system boot. Use this for elapsed-time measurements and timeouts without depending on wall-clock time.

return

uint64_t

Milliseconds since last boot. This value wraps after approximately 584 million years of continuous uptime.

timing_example.c

#include "anx/anx.h"

void app_main(void) {
    uint64_t start = anx_uptime_ms();

    // ... do work ...
    anx_delay_ms(500);

    uint64_t elapsed = anx_uptime_ms() - start;
    ANX_LOGI("APP", "Elapsed: %llu ms", elapsed);
}

Reboot Functions

`anx_reboot()`

Performs a graceful system reboot: flushes any pending filesystem writes, closes open peripherals, and resets the processor. Use this instead of a hard reset to avoid filesystem corruption.

return

void

This function does not return. Execution resumes from the beginning of app_main() after the boot sequence completes.

`anx_reboot_to_bootloader()`

Reboots the device directly into firmware flash mode. The device will appear as a firmware flashing target on its USB or serial interface and will not execute app_main() until a new firmware image is flashed or the device is power-cycled.

return

void

This function does not return.

Call anx_reboot_to_bootloader() only when you have confirmed that a firmware update tool is ready and connected. Entering flash mode without an active update session leaves the device unresponsive until power-cycled.

​app_main() Entry Point

​System Information Functions

​anx_firmware_version()

​anx_sdk_version()

​anx_device_id()

​Logging Functions

​Delay and Timing Functions

​anx_delay_ms()

​anx_delay_us()

​anx_uptime_ms()

​Reboot Functions

​anx_reboot()

​anx_reboot_to_bootloader()

`app_main()` Entry Point

System Information Functions

`anx_firmware_version()`

`anx_sdk_version()`

`anx_device_id()`

Logging Functions

Delay and Timing Functions

`anx_delay_ms()`

`anx_delay_us()`

`anx_uptime_ms()`

Reboot Functions

`anx_reboot()`

`anx_reboot_to_bootloader()`