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mabster 1 days ago [-]
I went to the page expecting to rant about how it's not actually credit card size because of the thickness and was for once pleasantly surprised! Kudos to the author! It looks great!
ghrl 21 hours ago [-]
I was thinking all that too and considering commenting about being sick of those credit card size claims, but after seeing the footage I am genuinely impressed. Great work there.
krauseler 16 hours ago [-]
Love how the point of this entire thing comes across!
majorchord 14 hours ago [-]
I'll be that guy I guess then... they stated on their page that credit cards are 0.8mm while the muxcard is 1mm and yet they still claim it is "literally the size of a credit card"... not to mention that they carved out an NFC card, not a credit card.
Yes it's still impressive either way, I'm not debating that.
rendaw 13 hours ago [-]
It said that the specification states 0.8mm, but that many real world cards are thicker. Are credit cards actually 0.8mm?
dayjaby 2 hours ago [-]
Did we read the same text? He wrote 0.76mm.
mabster 13 hours ago [-]
I did notice that difference too. But previous "credit card size" projects have all been several mm (as in couldn't fit a wallet designed for credit cards). So 1 mm is... pretty sweet!
asdefghyk 1 days ago [-]
This post - the title made me remember ... ( as a credit card is about the same size as a business card )
A Linux Business Card CD is a miniature, credit-card-sized optical disc containing a stripped-down, bootable Linux operating system. They hold around 50MB to 100MB of data and were highly popular in the early-to-mid 2000s
I had one of those - I think it is still in my office desk.
GJim 3 hours ago [-]
Business card CD ROM's were a nice idea in the day.....
.... trouble was they would often 'misfeed' when using a tray style CD Rom drive and jam in the mechanism, meaning you had to dismantle the drive to get the card out.
Understandably, this would quickly piss off people you gave the card to. This helped make the cards rather unpopular.
Seth Schoen (<https://news.ycombinator.com/user?id=schoen> at HN) was lead dev in building one of the best-known instances of these, the Linuxcare Bootable Business Card (LNX-BBC), and has occasionally commented on that here:
Just saw this and love how I got the 100th or so "Does it run DOOM?". Even now officially an issue on GitHub. Does that mean I now have to deliver?
insane_dreamer 38 minutes ago [-]
Yes ;)
Muhammad523 1 days ago [-]
> Does that mean I now have to deliver?
Well, if you'd like to, you're free to do so! If not, somebody else could do it. You're not your audience's slave
I know it was intended as a joke but still..
abdullahkhalids 1 days ago [-]
How optimal is the PCB density? Do you think there is significant room for improvement to have a smaller PCB and larger screen and/or battery?
krauseler 17 hours ago [-]
The PCB can be way smaller, but finding a flexible screen is the issue, there is a 2.9 inch one almost twice as big but the battery would suffer :/
IAmBroom 1 days ago [-]
So... it's not DOOM-complete?
Teenage Alan T. would be so disappointed... :D
sargstuff 15 hours ago [-]
Well, using something related/similar to turing-complete correspondence:
----
If it can fetch/display files from the internet, yes, it can run doom[5]. Or make use of curl, curl-doom[18]
-----
stripped down doom can run in 4MB (doom on a smart toothbrush[7]). ESP32 has support for up to 4MB external PSRAM[1]. ESP32 port of doom[2]. lcd screen might provide for faster refresh / less blury images under magnifying glass.
Alternatively, adding an expansion port to be able to use 'doomchip' might make it easier hide game play while at work[8] / stay awake between screen frame refreshes. (and/or simulateously play tetris & 1d pacman; add Badgey functionality[19] )
But should one go with micropython[3], reflectionsOS[4] or not waste space and use a 2 stage 512k bootloader for dns.doom[5]?
contikiOS[6] for dns.doom[5] might be the correct fit without needing to add 4mb psram / doomchip expansion port(s).
-----
Misc doomchip information:
doomchip non-tech article(2020)[11].
doomchip developer comments[12]. Should be able to get at least 2fps!
doomchip better expanded upon in a 'heads up, 7up' thread -> slice[9]/doomchip[10].
----
Surprised there's no dns doom.wad / I.D.Software Application (IDSA) rfc "Spit.wad: A DNS string encoding using Unicode for doom.wad graphics" version of rfc3492: "Punycode: A bootstring encoding of Unicode for Internationalizaed Domain Names in Appliations" (IDNA) [13]
(IDSA) rfc might permit formally unifying things like unicode-line-stacker[14], stacked diacretics generator[15], unicodeart[16] and "awesome symbols and characters in a bash prompt"[17].
Thanks! This project is cool enough that I think we can tolerate another thread about it, especially since that post didn't get too much frontpage time. I'll put a link to it at the top though.
w8vY7ER 38 minutes ago [-]
yer dang right
gnabgib 16 hours ago [-]
Is this an ops we shouldn't have put this dupe in the SCP, or an ops the original submission should have been a different URL?
dthdthdtejdz 18 hours ago [-]
Thanks! Arbitrary application of rules is nothing short of what I would expect from CCP LOVER DANG.
sargstuff 15 hours ago [-]
... but both threads are DOOMed ...
lxgr 1 days ago [-]
> A fully working computer that is literally the size of a credit card.
Nit: A (chip) credit card is already a fully working computer :)
ZiiS 1 days ago [-]
Only if it is inside a specially designed radio field and with no independent IO. Feels like a battery and IO justify the 'fully working' differentiation.
lxgr 1 days ago [-]
Interesting philosophical question: Is a tower PC that's not plugged into anything (neither power nor a keyboard or monitor) a computer? Does computation happen if nobody can perceive it? And is a computer a computer even between two CPU cycles?
> no independent IO
I would challenge that! How is a smartcard different from a server in a qualitative sense? Both get all their I/O over the network.
Some cards even have a display, fingerprint reader, or can blink an LED (the latter unfortunately only indiscriminately when powered up, not in response to any computation, I'm afraid).
Rohansi 1 days ago [-]
Is a bare SoC a computer? You can poke the pins to provide power and I/O.
The interesting thing about this project is that this computer can function independently within a credit card sized space.
sargstuff 15 hours ago [-]
asic computer doesn't have cpu cycles. So, a computer is still a computer between two cpu cycles.
IAmBroom 1 days ago [-]
I've never heard a definition of a computer to include its power source.
IO is of course required.
sargstuff 3 hours ago [-]
Think that was a early computation thing -> CRT memory[0][1]
Perhaps the 'city block' heaters requiring similar sized AC condensors to provide control over Maxwell's daemon was the inspiration for the unix daemon process.
Optical computing makes fuzzy computations so much easier -> outgassing[2]
The battery is likely to be squeezed quite a bit after this is put in my wallet, and in my pocket.
Lithium batteries do not like to be squeezed. They tend to signal their distress with some type of heat, usually accompanied with a small fire and probable smoke as well.
A distressed battery is very insistent upon everyone to see it's state of mind...
skavi 1 days ago [-]
This is discussed in the post.
victorbjorklund 2 hours ago [-]
Wow. This is actually credit card sized.
z3ugma 1 days ago [-]
Hidden in here is the coolest part, that the author made flex PCBs at home
firesteelrain 1 days ago [-]
Just in time for DEFCON. We built many of these types of badges
> For the first prototype, I soldered each wire individually...
I salute you sir. Did you have a better solution for later versions?
deckar01 1 days ago [-]
Prologium is depositing thin film solid state batteries onto flexible ceramic insulators. They have some demos of single cells that appear to be thinner than 1mm continuing to operate after bending in half.
That looks like it's the size of a smartphone. It's 7 times thicker... I'm not sure that qualifies as a little thicker, plus all the other dimensions.
jansan 1 days ago [-]
I think that there could be a wider screen if such formats are available. Once we have betavoltaic batteries, the entire card can be screen.
rbanffy 1 days ago [-]
I'm not sure beta voltaics will ever reach LiPo densities. All materials I know would be unwise to place in your wallet, or anywhere near your body.
If we are OK with a battery and a beta voltaic source, a tritium one is reasonably safe and can trickle charge the battery when the device is in deep low power mode. The battery can still be charged by the induction coil.
mmmehulll 1 days ago [-]
love this. would be cool if we can see and perform all kinds of banking txns on this. Think ledger but all in one card. Super cool. Even cooler would be card to card money transfer without use of swipe machines
resonious 1 days ago [-]
If "ledger on card" interests you, then you might enjoy Japan's FeliCa cards. They store balance locally on the card so you can pay very quickly, no network required.
abdullahkhalids 1 days ago [-]
Do these cards solve the electronic cash problem (in a completely different way than cryptocurrencies)? What I mean is that
- Are the card readers special/trusted issued by bank/govt in some way? Or you can transfer money from one card to another yourself fully offline?
- Is there any requirements that the transfers have to be eventually communicated to the bank by one of the parties to be fully resolved?
- Has someone managed to create fake cards with fake money in it, or this is impossible by design?
csande17 9 hours ago [-]
As I understand it, these cards work basically the same way as transit card systems in other countries, like the SF Bay Area's "Clipper" cards.
The overall model is similar to tap-to-pay debit cards. They're only used for consumer-to-business payments. When you tap the card, the card sends over an account number / signature / etc, which the merchant sends to a central clearinghouse to finalize the transactions.
The main difference is that the card itself keeps a running balance of how much money the customer has available to spend. In many cases, this gives the merchant enough confidence to e.g. let you through the train turnstile without actually waiting for the central clearinghouse to confirm the transaction. (I think in practice they usually send all the transactions in batches, daily or weekly or something.)
The readers do some trusted-computing/secure-enclave type stuff but are not especially hard to obtain; I think there have even been cases where companies like Nintendo have built them into consumer products, so that you could e.g. tap your card to your Nintendo 3DS to buy a video game.
I imagine there's a bit more security on the machines that let you load money on the cards, but it's probably not completely impossible to make a fake card. But the low value limit (usually a couple hundred dollars, depending on the card provider), the inability to get cash out of the system (often you can't even buy things like postage stamps), and the fact that you'll get caught relatively quickly (once the central clearinghouse notices the transactions don't match up) make it unattractive to do it in practice.
abdullahkhalids 3 hours ago [-]
Thanks for the detailed answer.
voidUpdate 1 days ago [-]
It seems like it might be a little expensive for a business card...
bird0861 1 days ago [-]
Let's see Paul Allen's card.
yesbabyyes 21 hours ago [-]
Or, it would be interesting to see how this would fare in American Psycho.
fph 1 days ago [-]
How do you recharge it? Do you have to swap the battery?
krauseler 1 days ago [-]
Hey, developer here :)
I used an ultra thin LiPo, so you can actually charge it. USB is obviously not an option but it uses magnetic pogo pins on the back side ^^
frankest 1 days ago [-]
Try NGK EnerCera for battery.
stavros 1 days ago [-]
This is great, and I love it, and I hate to be saying this, but it's not literally the size of a credit card, it's 0.2mm thicker.
krauseler 1 days ago [-]
Fair enough, but I acknowledged that and it's 0.24mm thicker if we want to be exact. Here's a quote from my Git Repo:
"Official ISO7816 smartcards are specified at 0.76mm thickness, but many real-world cards slightly exceed this in practice. The target for this project was simple: Stay around ~1mm total thickness and preserve the illusion of a normal card."
stavros 1 days ago [-]
Hey, works for me, I just got OCD from the title's usage of the word "literally".
iberator 1 days ago [-]
Run Unix v6 on it :) 16 bit and works with like 80kb of ram
__This__ is where all those trusted app parts should go - a smart card with e-ink display that can provide high security assurance level and where I won't mind that it's locked down because it has only one purpose.
__Not__ to my smartphone, effectively preventing me from modifying the system in the name of security. A banking app can use a card like this and on the display I could for example see where a transaction would go and then I could accept it, possibly even with a biometric identification.
This would enable me to keep my smartphone customizable and banking apps secure at the same time.
[apologies for the rant]
NetMageSCW 21 hours ago [-]
And it would communicate using?
aa-jv 1 days ago [-]
I want this, but only for one thing: email.
I already use an pwnagotchi, and it works great for this - but its a bit bulky.
If I can get this set up and working, it'll be my main interface to email.
acrophiliac 1 days ago [-]
dyi = Do Yourself It?
sargstuff 14 hours ago [-]
selfie thing.
suzukivenom 1 days ago [-]
legendary
pslab 1 days ago [-]
[flagged]
1 days ago [-]
swordlucky666 1 days ago [-]
[dead]
flintenmuschi 1 days ago [-]
[flagged]
goodpoint 1 days ago [-]
It's not a computer.
cbdevidal 1 days ago [-]
It’s got more horsepower than my first desktop computer
bigfishrunning 1 days ago [-]
In what way is it not a computer?
krauseler 1 days ago [-]
Right, it doesn't compute. Apologies for the lie.
antonvs 1 days ago [-]
Your definition of "computer" is incorrect.
mrbluecoat 1 days ago [-]
First thought: cool!
Second thought: e-waste
(same reaction as single-serve coffee pods, circa 2023)
krauseler 1 days ago [-]
Good point. Ideally it would be the opposite of waste if it can save you from several cards. But banks would never certify such a multi-card system unless a big company pushes it forward.
Otherwise I'm sure people might use this to hack some terminals :P
Yes it's still impressive either way, I'm not debating that.
A Linux Business Card CD is a miniature, credit-card-sized optical disc containing a stripped-down, bootable Linux operating system. They hold around 50MB to 100MB of data and were highly popular in the early-to-mid 2000s
More info at https://en.wikipedia.org/wiki/Bootable_business_card
https://en.wikipedia.org/wiki/REX_6000
.... trouble was they would often 'misfeed' when using a tray style CD Rom drive and jam in the mechanism, meaning you had to dismantle the drive to get the card out.
Understandably, this would quickly piss off people you gave the card to. This helped make the cards rather unpopular.
https://en.wikipedia.org/wiki/Shaped_compact_disc
<https://hn.algolia.com/?dateRange=all&page=0&prefix=false&qu...>
I’d love to also go the opposite direction, a full-sized laptop with an ESP32 running tiny386 and Windows 95 ^_^
https://www.hackster.io/news/he-chunhui-s-tiny386-turns-the-...
Was turned into something commerical (?2002[2])[1]. Perhaps modern version would be the old AMD cyrix chips?
-------------------------
[0] : http://boole.stanford.edu/cebit/
[1] : https://megagames.com/news/matchbox-pc-smallest-world
[2] : https://ptacts.uspto.gov/ptacts/public-informations/petition...
[3] : https://www.paloaltoonline.com/morgue/monthly/1999_May_26.MI...
Just saw this and love how I got the 100th or so "Does it run DOOM?". Even now officially an issue on GitHub. Does that mean I now have to deliver?
I know it was intended as a joke but still..
Teenage Alan T. would be so disappointed... :D
----
If it can fetch/display files from the internet, yes, it can run doom[5]. Or make use of curl, curl-doom[18]
-----
stripped down doom can run in 4MB (doom on a smart toothbrush[7]). ESP32 has support for up to 4MB external PSRAM[1]. ESP32 port of doom[2]. lcd screen might provide for faster refresh / less blury images under magnifying glass.
Alternatively, adding an expansion port to be able to use 'doomchip' might make it easier hide game play while at work[8] / stay awake between screen frame refreshes. (and/or simulateously play tetris & 1d pacman; add Badgey functionality[19] )
But should one go with micropython[3], reflectionsOS[4] or not waste space and use a 2 stage 512k bootloader for dns.doom[5]?
contikiOS[6] for dns.doom[5] might be the correct fit without needing to add 4mb psram / doomchip expansion port(s).
-----
Misc doomchip information:
----Surprised there's no dns doom.wad / I.D.Software Application (IDSA) rfc "Spit.wad: A DNS string encoding using Unicode for doom.wad graphics" version of rfc3492: "Punycode: A bootstring encoding of Unicode for Internationalizaed Domain Names in Appliations" (IDNA) [13]
(IDSA) rfc might permit formally unifying things like unicode-line-stacker[14], stacked diacretics generator[15], unicodeart[16] and "awesome symbols and characters in a bash prompt"[17].
-------------------------------------------------------------
[0] : "Can it run doom?" : https://canitrundoom.org/
[1] : https://docs.espressif.com/projects/esp-idf/en/latest/esp32/...
[2] : https://www.techeblog.com/doom-electronic-badge-emfcamp/
[3] : https://github.com/NoosaHydro/2.4inch_ESP32-2432S024/tree/ma...
[4] : https://github.com/frankcohen/ReflectionsOS[5] : https://undercodetesting.com/dns-can-run-doom-how-2000-dns-r...
[6] : https://contiki-os.org/
[7] : doom on a smarth toothbrush : https://www.youtube.com/watch?v=cO-Are8053g[8] : https://hackaday.com/2020/05/13/the-doom-chip/
[9] : https://github.com/sylefeb/Silice
[10] : https://github.com/sylefeb/Silice/blob/master/projects/READM...
[11] : doomchip article : https://www.techeblog.com/doom-chip-game/
[12] : https://threadreaderapp.com/thread/1258808333265514497.html
[13] : https://www.rfc-editor.org/info/rfc3492/
[14] : https://github.com/axesilo/unicode-line-stacker
[15] : https://codepen.io/lingyloll/pen/ooMaYO
[16] : https://www.unicodeart.com/gallery/
[17] : https://unix.stackexchange.com/questions/25903/awesome-symbo...
[18] : https://codeberg.org/xsawyerx/curl-doom
[19] : https://memory-alpha.fandom.com/wiki/Badgey
Nit: A (chip) credit card is already a fully working computer :)
> no independent IO
I would challenge that! How is a smartcard different from a server in a qualitative sense? Both get all their I/O over the network.
Some cards even have a display, fingerprint reader, or can blink an LED (the latter unfortunately only indiscriminately when powered up, not in response to any computation, I'm afraid).
The interesting thing about this project is that this computer can function independently within a credit card sized space.
IO is of course required.
Perhaps the 'city block' heaters requiring similar sized AC condensors to provide control over Maxwell's daemon was the inspiration for the unix daemon process.
Optical computing makes fuzzy computations so much easier -> outgassing[2]
------------------------------------------------------
[0] : https://spectrum.ieee.org/the-birth-of-ram
[1] : https://bunkerofdoom.com/lit/CRT-scopes/CRT_memory/index.htm...
[2] : https://spectrum.ieee.org/adhesive-outgassing-nasa-standards
But...
The battery is likely to be squeezed quite a bit after this is put in my wallet, and in my pocket.
Lithium batteries do not like to be squeezed. They tend to signal their distress with some type of heat, usually accompanied with a small fire and probable smoke as well.
A distressed battery is very insistent upon everyone to see it's state of mind...
https://www.kickstarter.com/projects/m5stack/cardputerzero
I salute you sir. Did you have a better solution for later versions?
https://prologium.com/tech/core-technology/
And yes, if you accept ~0.7FPS
If we are OK with a battery and a beta voltaic source, a tritium one is reasonably safe and can trickle charge the battery when the device is in deep low power mode. The battery can still be charged by the induction coil.
- Are the card readers special/trusted issued by bank/govt in some way? Or you can transfer money from one card to another yourself fully offline?
- Is there any requirements that the transfers have to be eventually communicated to the bank by one of the parties to be fully resolved?
- Has someone managed to create fake cards with fake money in it, or this is impossible by design?
The overall model is similar to tap-to-pay debit cards. They're only used for consumer-to-business payments. When you tap the card, the card sends over an account number / signature / etc, which the merchant sends to a central clearinghouse to finalize the transactions.
The main difference is that the card itself keeps a running balance of how much money the customer has available to spend. In many cases, this gives the merchant enough confidence to e.g. let you through the train turnstile without actually waiting for the central clearinghouse to confirm the transaction. (I think in practice they usually send all the transactions in batches, daily or weekly or something.)
The readers do some trusted-computing/secure-enclave type stuff but are not especially hard to obtain; I think there have even been cases where companies like Nintendo have built them into consumer products, so that you could e.g. tap your card to your Nintendo 3DS to buy a video game.
I imagine there's a bit more security on the machines that let you load money on the cards, but it's probably not completely impossible to make a fake card. But the low value limit (usually a couple hundred dollars, depending on the card provider), the inability to get cash out of the system (often you can't even buy things like postage stamps), and the fact that you'll get caught relatively quickly (once the central clearinghouse notices the transactions don't match up) make it unattractive to do it in practice.
I used an ultra thin LiPo, so you can actually charge it. USB is obviously not an option but it uses magnetic pogo pins on the back side ^^
"Official ISO7816 smartcards are specified at 0.76mm thickness, but many real-world cards slightly exceed this in practice. The target for this project was simple: Stay around ~1mm total thickness and preserve the illusion of a normal card."
Works on the RISC-V 32-bit processor, sometimes.
__Not__ to my smartphone, effectively preventing me from modifying the system in the name of security. A banking app can use a card like this and on the display I could for example see where a transaction would go and then I could accept it, possibly even with a biometric identification.
This would enable me to keep my smartphone customizable and banking apps secure at the same time.
[apologies for the rant]
I already use an pwnagotchi, and it works great for this - but its a bit bulky.
If I can get this set up and working, it'll be my main interface to email.
(same reaction as single-serve coffee pods, circa 2023)
Otherwise I'm sure people might use this to hack some terminals :P