AutoConnect features a built-in OTA function to update ESP module firmware. You can easily make the Sketch that equips OTA and able to operate with the AutoConnect menu. As the AutoConnectOTA class, which is compliant with OTA updates using a web browser as described in the ESP8266 Arduino Core documentation.
You will be able to import the AutoConnectOTA class into your sketch just by specifying AutoConnectConfig::ota. By incorporating the AutoConnectOTA class into your Sketch, you can have an OTA updating feature which able to updating binary sketch from the AutoConnect menu.
The AutoConnectOTA feature is implemented based on the Updater class of the ESP8266 arduino core library. Its Updater class is also supported by the ESP32 Arduino core, so you can commonly import AutoConnectOTA into the Sketch without being aware of the differences between ESP8266 and ESP32 modules.
!!! info "Limitation of AutoConnectOTA with authentication"
AutoConnectOTA does not support authentication in v1.1.5 yet. It is planned for inclusion in AutoConnect v1.2.0, which will support HTTP authentication.
To embed the AutoConnectOTA class into your sketch, basically follow these steps:
ESP8266WiFi.h
, ESP8266WebServer.h
and AutoConnect.h
as usual.[^1]setup()
function:
loop()
.#include <ESP8266WiFi.h> // Step #1
#include <ESP8266WebServer.h> // Step #1
#include <AutoConnect.h> // Step #1
ESP8266WebServer server; // Step #2
AutoConnect portal(server); // Step #3
AutoConnectConfig config; // Step #4
AutoConnectAux hello; // Step #5
static const char HELLO_PAGE[] PROGMEM = R"(
{ "title": "Hello world", "uri": "/", "menu": true, "element": [
{ "name": "caption", "type": "ACText", "value": "<h2>Hello, world</h2>", "style": "text-align:center;color:#2f4f4f;padding:10px;" },
{ "name": "content", "type": "ACText", "value": "In this page, place the custom web page handled by the Sketch application." } ]
}
)"; // Step #5
void setup() {
config.ota = AC_OTA_BUILTIN; // Step #6.a
portal.config(config); // Step #6.a
hello.load(HELLO_PAGE); // Step #6.b
portal.join({ hello }); // Step #6.c
portal.begin(); // Step #6.d
}
void loop() {
portal.handleClient(); // Step #7
}
[^1]:For ESP32, change the following items:
- Change the include directives appropriately for the ESP32 environment.
- Change ESP8266WebServer to WebServer.
!!! faq "How LED ticking during updates"
AutoConnectOTA applies LED ticking during updates automatically. The destination LED port and ticker drive depends on [AutoConnectConfig::tickerPort](apiconfig.md#tickerport) and [AutoConnectConfig::tickerOn](apiconfig.md#tickeron) specifying.
**IMPORTANT**
The AutoConnectOTA activates the ticker constantly regardless of the [AutoConnectConfig::ticker](apiconfig.md#ticker) value. If you want to stop the ticker output to GPIO during updates, give `0xff` to [AutoConnectConfig::tickerPort](apiconfig.md#tickerport).
AutoConnectOTA has implemented using AutoConnectAUX. So it occupies two URIs by default. An update operation page is assigned to AUTOCONNECT_URI_UPDATE and the binary file uploader for the update is assigned to AUTOCONNECT_URI_UPDATE_ACT. These symbols are defined in the AutoConnectDefs.h
header file as follows:
#define AUTOCONNECT_URI "/_ac"
#define AUTOCONNECT_URI_UPDATE AUTOCONNECT_URI "/update"
#define AUTOCONNECT_URI_UPDATE_ACT AUTOCONNECT_URI "/update_act"
Therefore, the normal Sketch that imports AutoConnectOTA while keeping the default, you cannot use the two URIs /_ac/update
and /_ac/update_act
for your specific. If you want to use the URIs for any purpose other than AutoConnectOTA, you need to override the AutoConnectDefs.h
definition at compile time. It can be overwritten by giving the build flags for platformio.ini as follows with the PlatformIO environment for example.
build_flags =
-DAUTOCONNECT_URI_UPDATE='"/YOURURI"'
-DAUTOCONNECT_URI_UPDATE_ACT='"/YOURURIACT"'
It will be born during AutoConnect::handleClient process. AutoConnect will evaluate the enabled state of AutoConnectConfig::ota each time the handleClient is executed, and if OTA is enabled then it creates an AutoConnectAux internally and assigns it to the update page. At this time, AutoConnectOTA is also instantiated together. The generated AUX page containing AutoConnectOTA is bound to AutoConnect inside the AutoConnect::handleClient process.
If you want to attach AutoConnectOTA dynamically with an external trigger, you can sketch like this:
This sketch imports the OTA update feature with an external switch assigned to the GPIO pin. While the trigger not occurs, AutoConnect OTA will not be imported into Sketch and will not appear on the menu list.
#include <ESP8266WiFi.h>
#include <ESP8266WebServer.h>
#include <AutoConnect.h>
#define TRIGGER 4 // pin assigned to external trigger switch
AutoConnect portal;
AutoConnectConfig config;
void setup() {
pinMode(TRIGGER, INPUT);
portal.begin();
}
void loop() {
if (digitalRead(TRIGGER) == HIGH) {
config.ota = AC_OTA_BUILTIN;
portal.config(config);
}
portal.handleClient();
}
!!! note "AutoConnectOTA cannot detach dynamically"
Once imported, AutoConnectOTA cannot be removed from the Sketch. It can be only excluded from the menu by overriding [AutoConnectConfig::menuItems](apiconfig.md#menuitems). In this case, the AutoConnectOTA instance remains as a residue.
Binary sketch files for updating can be retrieved using the Arduino IDE. Open the Sketch menu and select the Export compiled Binary, then starts compilation.
When the compilation is complete, a binary sketch will save with the extension .bin
in the same folder as the Sketch.
The legacy OTA method based on ESP8266HTTPUpdateServer without AutoConnectOTA is still valid. To embed the ESP8266HTTPUpdateServer class with AutoConnect into your sketch, basically follow these steps:
ESP8266HTTPUpdateServer.h
, also WiFiClient.h
, in addition to the usual directives as ESP8266WebServer.h
and AutoConnect.h
.[^2]/update
to the URI of the update dialog page.setup()
function:
ESP8288HTTPUpdateServer::setup
function, specifies the USERNAME and the PASSWORD as needed.loop()
.[^2]: The AutoConnect library provides an implementation of the HTTPUpdateServer class that ported from ESP8266HTTPUpdateServer class for ESP32 intention. It is contained the WebUpdate under the examples folder.
#include <ESP8266WiFi.h>
#include <ESP8266WebServer.h>
#include <ESP8266HTTPUpdateServer.h> // Step #1
#include <WiFiClient.h> // Step #1
#include <AutoConnect.h>
static const char HELLO_PAGE[] PROGMEM = R"(
{ "title": "Hello world", "uri": "/", "menu": true, "element": [
{ "name": "caption", "type": "ACText", "value": "<h2>Hello, world</h2>", "style": "text-align:center;color:#2f4f4f;padding:10px;" },
{ "name": "content", "type": "ACText", "value": "In this page, place the custom web page handled by the Sketch application." } ]
}
)";
ESP8266WebServer httpServer; // Step #2
ESP8266HTTPUpdateServer httpUpdate; // Step #3
AutoConnect portal(httpServer); // Step #4
AutoConnectAux update("/update", "UPDATE"); // Step #5, #6, #7
AutoConnectAux hello; // Step #8
void setup() {
httpUpdate.setup(&httpServer, "USERNAME", "PASSWORD"); // Step #9.a
hello.load(HELLO_PAGE); // Step #9.b
portal.join({ hello, update }); // Step #9.c
portal.begin(); // Step #9.d
}
void loop() {
portal.handleClient(); // Step #10
}
The built-in OTA update feature can update the firmware as well as upload regular files placed in the file system on the ESP module. It allows a regular file is uploaded via OTA using the Update of AutoConnect menu without adding a particular custom Web page that contains AutoConnectFile. This utilization is useful for the operation of transferring the JSON document of the custom web page definition, the external parameter file of your sketch, and so on into the target ESP module via OTA.
The built-in OTA update feature determines where to save the uploaded file according to the filename pattern. By default, a filename with ends a .bin
extension is subject to firmware updates. A file that has another extensions will be saved as a regular to LittleFS (or SPIFFS) in the flash.
The filename extension that should be treated as the firmware is defined as the AUTOCONNECT_UPLOAD_ASFIRMWARE
macro in AutoConnectDefs.h header file of the library source code. When dealing with another extensions for the updating file as firmware change this macro definition.
#define AUTOCONNECT_UPLOAD_ASFIRMWARE ".bin"
!!! info "Specify with the PlatformIO"
`AUTOCONNECT_UPLOAD_ASFIRMWARE` pattern will be embedded into the binary sketch is determined at compile time. The [**PlatformIO**](https://platformio.org/platformio-ide) build system allows you to change the pattern of the file extension for each project without modifying the library source code.
```ini
build_flags=-DAUTOCONNECT_UPLOAD_ASFIRMWARE='".bin"'
```
!!! note "Use a regular expression to specify the file extension"
By default, you can specify only one file extension to be treated as firmware in OTA updates. However, you can specify the file extension as a regular expression, but it consumes a lot of memory.
If the file extension pattern contains a regular expression, you need to enable the flag of [`AUTOCONNECT_UPLOAD_ASFIRMWARE_USE_REGEXP`](https://github.com/Hieromon/AutoConnect/blob/master/src/AutoConnectDefs.h#L277) in `AutoConnectDefs.h`. Also, the `AUTOCONNECT_UPLOAD_ASFIRMWARE` definition as a regular expression is treated as a replacement string for the **#define** directive for C++ preprocessor, so the backslash must be escaped.