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Potentially, one of the great things about having a device connected to the network is that you can update it remotely. However, how do you make that happen? If you use the Arduino setup for the ESP8266 or ESP32, you might try [scottchiefbaker’s] library which promises to make the process easy.

Adding it looks to be simple. You’ll need an include, of course. If you don’t mind using port 8080 and the path /webota, you only need to call handle_webota() from your main loop. If you want to change the defaults, you’ll need to add an extra call in your setup. You also need to set up a few global variables to specify your network parameters.

The only caveat is that long delay statements in your loop can block things from working and aren’t a great idea anyway. If you have them, you can replace all your delay calls with webota_delay which will stop the system from ignoring update requests.

The code started from a different online tutorial but packaged the code up nicely for reuse. To do an update, simply navigate to the device with a web browser and use the correct port number and path. From there you can upload a new binary image taken from the Arduino IDE with the export compiled binary command.

The only concern we saw was the code didn’t appear to authenticate you at all. That means anyone could load code into your ESP. That might be ok on a private network, but on the public Internet it is surely asking for trouble. The original tutorial code did have a hardcoded user and password, but it didn’t look very useful as the password was in the clear and didn’t stop you from uploading if you knew the right URL. Dropping it from the library probably makes sense, but we would want to build some kind of meaningful security into anything we deployed.

If you have a network connection, we’ve seen the same trick done with a normal Arduino with a wireless chip. You can even do it over WiFi but using an ESP8266 which you’ll then want to be able to update, too.

A few months back we first brought word of the progress being made in unlocking the SMART Response XE, an ATmega128RFA powered handheld computer that allowed teachers to create an interactive curriculum in the days before all the kids got Chromebooks. Featuring 2.4 Ghz wireless communication, a 384×160 LCD, and a full QWERTY keyboard, schools paid around $100 each for them 2010. Now selling for as little as $5 on eBay, these Arduino-compatible devices only need a little coaxing and an external programmer to get your own code running.

The previous post inspired [Larry Bank] to try his hand at hacking the SMART Response XE, and so far he’s made some very impressive progress. Not only has he come up with his own support library, but he’s also created a way to upload Arduino code to the devices through their integrated 802.15.4 radio. With his setup, you no longer need to open the SMART Response XE and attach a programmer, making it much easier to test and deploy software.

[Larry] has written up a very detailed account of his development process, and goes through the trouble of including his ideas that didn’t work. Getting reliable communication between two of these classroom gadgets proved a bit tricky, and it took a bit of circling around until he hit on a protocol that worked.

The trick is that you need to use one SMART Response XE attached to your computer as a “hub” to upload code to other XEs. But given how cheap they are this isn’t that big of a deal, especially considering the boost in productivity it will net you. [Larry] added a 5 x 2 female header to his “hub” XE so he could close the device back up, and also added a physical power switch. In the video after the break, you can see a demonstration of the setup sending a simple program to a nearby XE.

Between this wireless bootloader and the Arduboy compatibility covered previously, we’d suggest you get your SMART Response XE now. We wouldn’t be surprised if the prices of these things start going up like they did with the IM-ME.

An Arduino and a data radio can make a great remote sensor node. Often in such situations, the hardware ends up installed somewhere hard to get to – be it in a light fitting, behind a wall, or secreted somewhere outdoors. Not places that you’d want to squeeze a cable repeatedly into while debugging.

[2BitOrNot2Bit] decided this simply wouldn’t do, and decided to program the Arduinos over the air instead.

Using the NRF24L01 chip with the Arduino is a popular choice to add wireless communications to a small project. By installing one of these radios on both the remote hardware and a local Arduino connected to the programming computer, it’s possible to remotely flash the Arduino without any physical contact whatsoever using Optiboot.

The writeup is comprehensive and covers both the required hardware setup for both ends of the operation as well as how to install the relevant bootloaders. If you’re already using the NRF24L01 in your projects, this could be the ideal solution to your programming woes. Perhaps you’re using a different platform though – like an Arduino on WiFi? Don’t worry – you can do OTA updates that way, too.



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