M1 App SDK

Build external apps for the Monstatek M1. Apps are relocatable ARM ELF files (.m1app) loaded from the SD card and run as FreeRTOS tasks on the M1's Cortex-M33, calling firmware functions resolved at load time via a symbol table.

Runs on app-loader firmware such as M1-firmware-connected.

What's in this SDK

• include/m1app.h — the full app API: display (u8g2), input, timing, memory, audio, LEDs, GPIO/I2C/SPI, IR, NFC/RFID/Sub-GHz, crypto, file I/O, Flipper file parsers, and a new HTTP client (see below).
• include/m1app_conf.h — header-only SD config parser (m1conf_load/get/ get_n/split) so apps are configured from .conf files, no recompile.
• examples/ — hello world, game template, coin flip, flappy bird, etc.
• apps/ — four homelab/device-integration apps (below).

HTTP client (new)

Apps can call LAN/cloud device APIs over WiFi. The ESP32-C6 (ESP-AT firmware) does the TCP/TLS; the firmware just formats AT+HTTPCLIENT.

int m1_http_get(const char *url, char *resp, int resp_size);
int m1_http_post_json(const char *url, const char *json_body, char *resp, int resp_size);
int m1_http_request(int method, int content_type, const char *url,
                    const char *headers /* e.g. "Authorization: Bearer …" */,
                    const char *body, char *resp, int resp_size);

Returns response-body bytes (≥0) or a negative M1APP_HTTP_ERR_*. Requires the device to be on WiFi (Main Menu → WiFi → Config).

Bundled apps (apps/)

App	What it does	Config file
ha_remote	Toggle Home Assistant entities (authenticated)	ha.conf
fleet_status	Up/down reachability board for your LAN hosts	fleet.conf
webhook_buttons	Fire configurable GET/POST webhooks	hooks.conf
device_status	Poll authenticated JSON endpoints, show a value each	status.conf

Each app ships a *.conf.example — copy it to 0:/apps/<name>.conf on the SD card and edit it (URLs, tokens, entity IDs).

Build

sudo apt install gcc-arm-none-eabi        # or brew install arm-none-eabi-gcc
make APP=apps/ha_remote                    # -> apps/ha_remote/ha_remote.m1app
make APP=examples/hello_world              # build an example

Deploy

1. Flash app-loader firmware (M1-firmware-connected) + ESP-AT (with HTTP support) to the ESP32-C6; connect WiFi on the device.
2. Copy *.m1app and the edited *.conf to 0:/apps/ on the SD card.
3. On the M1: Main Menu → Apps → pick your app.

Pre-built .m1app files for the four apps are attached to the Releases.

Writing your own app

#include "m1app.h"
M1_APP_MANIFEST("My App", 512);            /* name, stack in 32-bit words */

int32_t app_main(void *context) {
    u8g2_t *u8g2 = m1app_get_u8g2();
    while (1) {
        m1app_display_begin();
        do { u8g2_SetFont(u8g2, u8g2_font_6x10_tr);
             u8g2_DrawStr(u8g2, 10, 30, "Hello!"); } while (m1app_display_flush());
        if (game_poll_button(100) == M1APP_BTN_BACK) break;
    }
    return 0;
}

See include/m1app.h for the complete API and the list of available fonts.