In article <nkarvp$1oor$
2...@gioia.aioe.org>, Someone Somewhere wrote:
> Any idea who the SIM manufacturer is?
No, I did wonder.
> It would normally be written on the packaging somewhere ...
You'd think, wouldn't you? No, there's nothing. Three's packaging makes
no mention of the SIM maker, and the card itself has nothing that looks
like a maker's name -- neither the full-size card nor the micro-SIM
itself.
There is a sequence of characters "GA6J100" on the SIM just below the
contact pad that just might be a model number, but it's not one I
recognize.
> the usual suspects would be Gemalto, Oberthur, Gieske and Devrient,
> Morpho etc, but it may well be an odd one.
Interesting to know ... the last time I looked at smartcards in any
detail GemPlus and Schlumberger had not yet merged to form GemAlto! (I
wrote a lot of code to handle GemPlus MCOS, MPCOS, and GPK family cards,
at one time).
> Any thoughts on voltage? From vague memory there have been at least
> 3 different standards over the years, and I know some devices needed
> SIMs that supported the higher voltages.
That's an interesting question. The modem just says that it supports a
standard USIM interface, with no mention of voltages. The SIM card
receptacle is actually on the Thinkpad's motherboard and not directly
part of the modem, so possibly the supply voltage comes from the laptop
and not from the modem (it would be odd if the supply voltage didn't
match the signal voltage, though).
I'd assume (perhaps incorrectly) that the USIM spec would provide some
means for the card and the cardreader to "agree" a suitable voltage ...
I'm not sure how much the USIM spec differs from standard ISO 7816, but
ISO 7816 sets down how cards should agree protocols and baud rates and
suchlike -- if voltages vary between cards as you say I'd hope that the
interface standard says how that should be handled. Perhaps that's
hopeless optimism on my part?
In the last couple of days I've upgraded the netbook to the same version
of Ubuntu that the Thinkpad is running (though only the 32-bit version,
as the netbook has a crummy Atom Z520, which doesn't support 64 bits)
and it still accepts the Three SIM quite happily. That's using a
different modem, with a different interface (mini-PCIe, though again in
USB mode), of course, so there are still differences between the
systems.
I'd ask Three's support whether they had any experience of their "Trio"
SIMs working in a Huawei ME906s-158 modem if I thought they had anyone
technical enough to understand the question in a customer-facing role.
This is getting frustrating!
Thanks for your continued interest.
--
Cheers,
Daniel.