Today's mood: I'm taking apart a Computer Device that is in that fun category of "you can post about this, but don't tell anyone where it's from". I have to remove two printers (!) from within it, several springs, a whole complicated folding mechanism, and I find that in the auxiliary board (that powers/controls the printers), there's actually a hidden USB device. There's an internal USB port that you can't access without fully disassembling the unit, and /it has a flash drive in it/.

I check my main (win10) laptop, it says no, can't read this, it's some linux partition. So I dig out my linux laptop, find the charger, find the missing power cable for the charger, finally get that plugged in and booted, and attach the mystery flash drive...

@foone wait, is this Device a voting machine?
i messed around with one ("did research into" lol) back in undergrad that had two rather different thermal printers inside

@flamingspork It's some kind of order-printing-thing, where you select items you want and it prints out receipts. basically a PoS but without money being involved, since it's from some kind of company cafeteria

well, that was certainly worth it!

lemme just quickly put this fucker back together.

oh fuck me it's an NXP i.MX 6.

I've used these before in an embedded product. I'm not exactly a fan. Their graphics stack is deeply stupid.

specifically this is a dual-core ARM Cortex-A9 at 1ghz. It's got a DDR3 controller on-die, this variant has both the VPU (for video decoding) and GPU (for 3d/2d graphics) as-well.

and hey look here is some DDR3: Micron MT41K128M16JT.

256 megabytes each, with 4 of them, so we've got 1 gigabyte in total.

@WestLawns no, but it has two printers inside it!

this thing has some fun design decisions.

the auxiliary board has two ethernet ports, and the main CPU board has one.

Why's it need so many ethernets? Simple: The main board is in the screen, and the auxiliary board is right where they need the port on the outside. So the main board is just plugged into the auxiliary board with a cat5 cable, and then the other ethernet port sticks outside the case

the two ethernet ports on the auxiliary board are not electrically connected to anything on the board, except each other.

it's just a keystone jack, except soldered to the board!

it looks like they did something with the USB as well, with two USB-A ports on the aux board and a (forbidden!) male-to-male USB-A cable connecting the aux to the main board, but nope! they put a USB hub on there.

It's a SMSC (now Microchip) USB2513B USB 2.0 hub

the MCU on the aux board is a Micron MK20DX256VLL7: It's a Kinetis K20. That's a 72mhz microcontroller, ARM Cortex-M4.
(This is a very microcontroller device compared to the running-linux-CPU of the other chip)

@foone so is the hub just being used as a repeater, or is it actually driving multiple ports/devices?

@lackthereof It runs two ports and I suspect the MCU as well

there's a hidden micro-USB port on the main board. interesting.

Main storage for the system is this Kingston eMMC chip, a KE4CN3K6A 8 gigabyte chip.

The wifi is a Murata Electronics LBEE5ZSTNC, providing 802.11b/g/n WiFi & bluetooth.

It's also got this set of dip switches for subpanel ID.

It also calls itself an FST9800 Controller, which has no hits on google.

they also do that weird thing plenty of small-run products do where the internal power supply is just an external power supply they hid inside the box.

It's a 24v DC power supply, just mounted internally with a cut-out for the mickey-mouse connector.

@foone that does rather identify the object, are we allowed to say what it is if you don't say where it came from?

@abrasive sure!

@foone apparently it is an Ithaca 9800 Food Safety Terminal! here is the maintenance manual, although sadly I don't see anything juicy in it (other than the hamburger): https://device.report/m/28085cbe6bc2d4b023ef8c2cc388c436e693eb21214dcfd01079bd601e81c73c.pdf

huh. one of the cables is just to reroute the ethernet activity LEDs to the secondary board so they can be seen from outside the printer.

lotta work for some blinkies, but I guess not having blinkies is a support nightmare