On Fri, 9 Jan 2004, Jesse I Pollard wrote: > On Fri, 9 Jan 2004, Krister Walfridsson wrote: > > Right, but communication with the card is done though a packet based > > interface. I would guess that the USB readers using the the USB-Serial > > converter are the first generation USB readers, that was made by > > just repackaging the existing serial readers, and let the vendors use > > their existing PC/SC drivers for Windows. Most new USB readers should > > use the CCID. > > That is true. This applies to the current round of cards which are ALL > serial. (backward compatability will be a real booger of a job to do). > Counting pads, I don't think they are 8 bit parallel (though they might > be - depends on how many grounds/power pads there are).
My point is that the applications do not use a serial interface to the cards -- all communication is (logically) done with APDU "packets". And you do not talk directly to the card's serial interface when using serial readers either, since the timing to the card is too delicate to be left to the computer. So the readers do a varying amount of work themselves, and do often handle things like re-transmissions and the procedural NULL byte. So the reason smart card readers have been using the serial port is because it has been the most convenient interface on the PC, and has nothing to do with the smart cards being serial. ISO is working on adding USB capabilities directly to the cards. I have not been following this work, but the document (7816-12 "Part 12: USB Interface for integrated circuit(s) cards with contacts") is expected to reach FDIS (Final Draft International Standard) this year. /Krister _______________________________________________ Muscle mailing list [EMAIL PROTECTED] http://lists.musclecard.com/mailman/listinfo/muscle
