first impressions of the Lego smart brick, before I do any actual tearing down: wow, I forgot how good they are at working with plastic.
-
alright let's dump the ARC chip now
-
first impressions of the Lego smart brick, before I do any actual tearing down: wow, I forgot how good they are at working with plastic. the injecton molding remains impeccable, at least for this specific piece (I know about their recent QC issues elsewhere)
it's hard for me to look at the positively microscopic (I am literally using a microscope to look at it) "Li-Ion" lettering and think of anything but "showing off!"
(treehouse doesn't let me attach the full size images, you can grab them here: front, side)
@whitequark but the most important question remains unanswered: Can you make it play actual star wars sounds instead of the unintelligible gibberish now?
-
alright let's dump the ARC chip now
not my best work but it should do the trick
feat. comically big q-tip
-
not my best work but it should do the trick
feat. comically big q-tip
@whitequark oh lol I thought it was a cat’s paw
-
@whitequark oh lol I thought it was a cat’s paw
@dev that would be a really small cat
-
not my best work but it should do the trick
feat. comically big q-tip
unfortunately, i could not access JTAG. i think i ran out of time i have for playing with this board, good luck @ everyone else
shout out to:
https://github.com/nanash1/smart_brick
https://codeberg.org/shelfofsheelfs/SMART-Brick
for doing good work! -
unfortunately, i could not access JTAG. i think i ran out of time i have for playing with this board, good luck @ everyone else
shout out to:
https://github.com/nanash1/smart_brick
https://codeberg.org/shelfofsheelfs/SMART-Brick
for doing good work!after reading the datasheet a bit more carefully, i know why i couldn't: the JTAG port is simply not exposed unless the firmware configures the pin mux that way. i'd have to dump the firmware in some other way
-
after reading the datasheet a bit more carefully, i know why i couldn't: the JTAG port is simply not exposed unless the firmware configures the pin mux that way. i'd have to dump the firmware in some other way
@whitequark oh how fun, but makes sense for such a pin-constrained device. Is there any other way to access it or is the chip just impossible to reprogram it if it doesnt expose JTAG?
-
@whitequark oh how fun, but makes sense for such a pin-constrained device. Is there any other way to access it or is the chip just impossible to reprogram it if it doesnt expose JTAG?
@cinebox it has a bootloader which I assume is how it's programmed by LEGO; I think I know how to trigger that but I just wanted to connect JTAG because it was more challenging to solder these tiny wires and I'm bad at doing it
-
after reading the datasheet a bit more carefully, i know why i couldn't: the JTAG port is simply not exposed unless the firmware configures the pin mux that way. i'd have to dump the firmware in some other way
@whitequark could it have booted in cJTAG mode?
-
@whitequark could it have booted in cJTAG mode?
@ldcd the datasheet explicitly says the JTAG pins are GPIO'd
-
here's a video that shows in more detail the moldwork in the transparent plastic part
@whitequark are the pips on top buttons too?
-
@whitequark are the pips on top buttons too?
@lenary no, just normal lego brick shape
-
not my best work but it should do the trick
feat. comically big q-tip
@whitequark I know this seems like an ordinary jump to you but if I managed to get one as clean as this, I'd feel like a goddamn hero
I ruined a beautiful rf01(one of those xbox 360 donor rf recievers wired through usb) with my soldering
Then it died but I think that was because I wasn't supplying the right power the right way(iirc it wanted a stable 3.3v and I just gave it a nodemcu 3v3) which was a common problem on these boards
-
@whitequark I know this seems like an ordinary jump to you but if I managed to get one as clean as this, I'd feel like a goddamn hero
I ruined a beautiful rf01(one of those xbox 360 donor rf recievers wired through usb) with my soldering
Then it died but I think that was because I wasn't supplying the right power the right way(iirc it wanted a stable 3.3v and I just gave it a nodemcu 3v3) which was a common problem on these boards
@sounddrill if you're in the area I can teach you how to do it as cleanly as this. nothing special about it
-
finally done. no shorts and (as far as i can tell under mag) no opens
@whitequark This is wonderful
-
@whitequark but the most important question remains unanswered: Can you make it play actual star wars sounds instead of the unintelligible gibberish now?
@triplef that would have to involve the totally undocumented ASIC
-
@triplef that would have to involve the totally undocumented ASIC
@triplef honestly the easiest way would be to join LEGO and get all the docs. I probably could do this if I wanted
-
@sounddrill if you're in the area I can teach you how to do it as cleanly as this. nothing special about it
@whitequark I'm way out in South India but hey, thanks!
I first learned basics of PCB design years ago over a discord server so I'll be sure to ask if I need to pick something up
-
@ldcd the datasheet explicitly says the JTAG pins are GPIO'd
@whitequark yup i only mention because TMSC (GPIO11) and TCKC (GPIO10) both go straight to vias (and then maybe to the array of testpoints on the back?); Wheras TDO (GPIO9) seems to go to the flash and TDI (GPIO8) seems to go ??.
So I was thinking there's a chance they might be explicitly configuring it as cJTAG and using it for a boundary scan test after manufacture.
