Carambola 2 Images




Yippee, I finally received a batch of Carambola2s in the mail today.  I had a couple that were ready for me to pick up a couple of weeks ago but didn’t get it until Saturday…

So similar to the TL-WR703N I’ve prepared a standard image with most of the hacker stuff baked in for people to try out with a limited repository (not as comprehensive as the TL-WR703N one and definitely not compared to the 8devices/OpenWrt ones) compiled and available online.

I’ve also build the Image Builder again for people to remix and make their own images without doing the full OpenWrt build.

The following have been tried and seem to work :

  • Python
  • Python-libusb1
  • Pyserial
  • Python HTTP Server
  • USB Serial (ACM)
  • WiFi, Eth0, Eth1, Buttons

Don’t expect anything not to work, but it was worth noting 🙂

Someone really should donate me a 3G modem to test with…

15 thoughts on “Carambola 2 Images”

  1. Thanks Madox!
    FYI – the first link is pointing to the same file as the second link. But a cut/paste worked.

  2. The Carambola 2 is your homebaked version on the TL-WR703N? With extra usb ports? That’s kind of awesome. How much did they cost you each? Were the boards already populated, etc?

    PS – at the Adelaide Hackerspace now, troubleshooting our mobile guestbook.

    1. Nope, not mine – The Carambola2 is made by 8devices ( ). They also make that motherboard, only has 1 USB on it though but good enough price for a supported module. Someone else has made a custom board using a cheap hub for more USB though…

  3. “I’ve also build the Image Builder again for people to remix and make their own images without doing the full OpenWrt build.”

    This sounds extremely tempting – how would one go about that exactly? I’m currently trying to compile openwrt for carambola2 with lighttpd / vsftpd / mysql and php and have failed 4 times in a row (hence wasted almost 24 hours compiling) and if your tool could make the compiling any easier, I’d be the happiest guy on the planet 😉

    I’ve so far tried to compile the above said setup using menuconfig multiple times and there were always errors in the late building phase. (once it was mysql that said files were missing, another time some sound module even though I’ve never even included that)

    How does your tool work exactly? I’m trying to glean from the contents of your upload but without actually being able to execute it on a 64bit linux machine it may be a little too hard to guess how I would have to use it.

    1. Hi the ImageBuilder is basically a compiled set of packages which can be packaged up into image. However, I don’t think I’ve compiled mysql and php into my ImageBuilder set so it won’t work for you. Why MySQL and PHP anyway? For something like Carambola2, wouldn’t something more lightweight be more suitable?

      Sometimes it is worth just running the make again and again 🙂 Then when it is the same error, run again with V=99 to see what the problem is. Quite often it is just an undeclared pre-requisite and that hasn’t finished compiling yet…

      1. Wow thanks for the fast reply Madox!

        Oh ok I get it now, sounds pretty great! I have however now finally been able to get OpenWRT to compile! (without mysql, but lighttpd and php are already in there)
        Basically I used exactly the same settings as before, just this time I used a 32bit Ubuntu VM – and it worked.
        I’m now looking for a way to build just the missing MySQL package so I can install that on my carambola later without now building the entire image again (and maybe failing again lol)

        The reason I’m trying to setup a whole lamp stack is that I’d like to get some small webapplication up and running for myself (smartphone controlling some lights with a nice interface ). Once I got it working, I’ll start optimizing.

        I’m thinking of writing my own HTTPD which will interact with an application of my own writing to create dynamic content for the webinterface. (instead of using lighttpd + php).
        MySQL would be very useful though, as I’m having another project in mind that would make use of ~2000 entries with about 5 columns each. – Of course I could code something like that by mysql, but just to try and experiment it would be nice if I could get it working with MySQL first 😀

        1. Still think it is overkill 🙂 sqlite should work full well…

          What lights are you controlling? I’ve got a bunch of LEDs connected to a TL-WR703N which is the carambola2’s cousin controlled by a Web interface but I was testing speech recognition… slight lag though…

          1. Holy moly, that’s a cool idea! What entity is it that does the speech processing here exactly?
            I won’t need mysql per se, it’s just the only database I’ve worked with so far. Anything that lets me send use SQL commands or something similar will do -> i’ll try sqlite then.

            Right my lights are just one long RGB led strip, and currently I’m using an avr + enc28j60 to control the RGB values of the strip from an app on my phone.
            The next step would be to implement an HTTPd on an AVR, which is actually not that big a deal when doing it with a simple interface. I’d like to code a webapp using html5 elements though and I think it’ll end up in quite a few requests for the AVR, which it might not be able to handle, so I’m switching to a carambola.

            Also: I’m gonna be travelling in South Korea and Taiwan this summer and will be on a lookout for some LED strips which let me control every led individually. I’m thinking of having some huge LED display on my wall which could either just be a static light but which would also offer the ability to play some animations.
            For this setup I’m thinking carambola as a master that generates the data and sends them to a bunch of AVR over SPI or Ethernet (UDP in that case) for them to display…
            Also, I’m gonna try to do some audio streaming with the Carambola2. – The problem however is that I would REALLY like to use an i2s dac instead of a usb one(for sake of higher quality..) and I can’t seem to find any documentation for the Atheros’ chipset’s i2s, so writing a driver will probably be quite a challenge I guess (or even impossible)

          2. I would recommend you buy the LED strips online and not what you might find locally in Asia. WS2801s can be bitbanged rather nicely by the Carambola2, or WS2811s if you don’t mind using a slave processor like the AVR or a Teensy.

            Have a look at & both of which use addressable LEDs connected to a router 🙂

            I just got my USB soundcards today, why would i2s be better than a USB one in terms of quality?!?!

  4. Besides, if I may ask (sorry to ask here)
    which one of the generated .bin files is actually the one that I need to flash?
    I got:

    I selected Luci during build but I suspect only one of the generated .bin
    is the right one that actually contains luci as well?
    Please give me a hint so I don’t brick my cara2 – thanks 🙂

      1. thanks! 🙂

        I’m gonna write here about the leds(I think it’s too deeply forked, can’t see a reply button there ^^)

        Why haven’t I found this on your page before 😀 it’s pretty much what I’m thinking about doing – connecting a bunch of those addressable strips and connecting one strip next to the other to get a matrix.

        I’m surprised to hear that the WS2811 works well – I thought it had pretty tight timings and would be one wire so I thought it’ll be difficult to synchronize using just a carambola. Happily surprised!

        I was considering some driver IC that uses SPI (LPD8806 for example). In the case that I would get too many leds to handle with just the carambola I think I’ll get an ethernet+atmega interface for each strip and parse data from UDP packages.
        (I have a solution for that which is partially already online It takes data from udp packages and outputs the frame on spi / i2c / parallel etc. Sending part on the carambola2 which does the calculations for animations would be netcat.

        I don’t think USB soundcards have bad quality in general, but I’d like to have a small solution and can’t seem to find anything that is small yet has a good DAC like a wolfson built in.

        My dream setup would be carambola2 + wolfson dac(i2s) + usb storage on the usbport

  5. Hello,

    I can’t find any contact info in the site so forgive me for using the comment section. I’m Algen, I work with engineering website and would love to do an exchange of website links (with your website: and feature you as a site of the day on EEWeb (you can see an example here Is this of interest to you?

    Hope to hear from you soon.


    Algen Dela Cruz

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