# Debugging OpenSC

    opensc-tool -l

will give you a list of readers opensc has found. If your reader isn't listed, you have a problem with that reader. For OpenCT see http://www.opensc-project.org/openct/wiki/TroubleShooting for details. For PCSC/Lite see it's documentation (FIXME: a link would be nice). For CT-API readers, edit the opensc.conf and make sure the reader is properly configured. If it still doesn't help, increase debugging to level 5 or higher in opensc.conf, run "opensc-tool -l" again and send a debug log to the mailing list (see ContactInfo? for details).

FIXME: more help for debugging opensc.

## Unsupported INS byte in APDU

This is a common error message. The best translation is:

    Sorry, we don't know that card.

Each card is identified by it so called ATR ("Answer to reset"). You can get this identification code by running

    opensc-tool --atr

OpenSC contains a compiled in list of atr it knows in each card driver. To check if any card driver knows about your card, please run

    opensc-tool --name

So if that name is "Default driver for unknown cards" then either your card is not supported at all, or it is a brand new version of an old and supported card, and if it is compatible with the older version it might work.

In case it is only a new version, but still compatible, you can edit opensc.conf and configure some driver to also accept this new atr. opensc.conf already contains a configuration example, you only need to change the atr and driver and enable it. Here is that example code:

            # GPK card driver additional ATR entry:
            card_driver gpk {
                    atr = 00:11:22;
            }

Replace "gpk" with the card driver of your card and "00:11:22" with the atr printed by "opensc-tool --atr". WARNING: this can damage your card and render it useless (in case the driver is not compatible with your card). So don't do this, unless you are absolutely sure of what you are doing. If you are not sure, please contact the OpenSC Team (see MailingLists for details).

Also note: more and more drivers have internal flags, for example for subtypes of cards or for certain properties, like whether or nor a card can generate keys (very old smartcards can't do that). Currently it is not possible to set those flags in the config file, so often it might be necessary to edit OpenSC source code and recompile OpenSC.

If you have a card with some new format, and you are not sure whether some emulation layer in OpenSC supports it, you can try this command and send us the output:

    opensc-tool -f

It will read all directories, files, permissions and file content, i.e. all public content on the card, thus we can have a look, maybe it is something we already know.