Tag Archives: embedded devices

Zagreb’s Public Transportation device details

Ako se pitate što vrte ZETovi tramvaji, to jest uređaji za poništavanje karata, čitajte dalje.
Rest of this post is in English.

Ticket checkout devices installed during 2009 in Zagreb’s trams and buses are already known to run X Window System. I have identified and photographed it during an obvious malfunction. Another one has happened today.

In a tram on line 4, I took the shots attached to this post. They identify the hardware as running on Atmel’s BIOS. CPU is also Atmel’s; they contain AT91SAM9263 CPU at 200 MHz. Devices contain 64MB of SDRAM, and for storage purposes, 256 MB of NAND flash. They seem run U-Boot 1.1.5 from May 2 2008. At least I think that’s a U; as you can see it was sliced off. Screen calibration fail, much?

Because it runs U-Boot, they also probably run Linux, on which they run X11, on which they run their custom GUI.

For those who don’t know (those outside Zagreb), these are new smartcard-reading devices used to track “subscribers” and to charge “non-subscribers”. You’re supposed to put your card on the device in order for it to scan your ZET-issued smartcard, and charge you/record your movement accordingly.

Some more technicalities:

  • AT91SAM9263 is an ARM9-based system-on-a-chip with 200 million instructions per second, 27 DMA controllers, AC97 audio controller, USB 1.1 host,  compact flash, and more. See link for more info. A powerful little piece of hardware indeed; this means there could be literally anything in there.
  • U-Boot is a part of Linux4SAM, which led me to conclude they run Linux.
  • While they might, I doubt they run a GNU system. While it’s probably Linux, as it’s an embedded system I doubt it’s GNU; or at least GNU comprises a much smaller part of it than on desktops. Which is why in text above I’m calling the system just Linux and not GNU/Linux 🙂
This is all so fascinating. I hope someone does an interview with the designers of the system, and I’d love even more if I could meet those engineers. I’d love to hear some more inside info and some official specs. It’s quite sad that I’m basing all my info on system crashes.

Trams in Zagreb run (at least) X11

Raw unrotated cellphone pic, just taken.
These cool, touchscreen-enabled, smartcard-reading devices for ticket sales/verification seem to have only one flaw: a chunk of Engrish (‘select zone or aproach [sic] card’). They even run X11, probably on a UNIX! I suspect each device is just a dumb terminal that gets imagery over network, since other devices in the tram had proper (or improper, if switched to English) GUI displayed.