Smartcard Lib for Arduino compat. boards Files

This is currently a work in progress.

Currently it is possible to communicate with a smartcard directly connected to a Arduino or via a TDA8024T (or compatible chips. e.g. DS8024).

All tests have been done with a smart card slot connected directly to the Aruino board. 

Working:
- Activation of asynchronous and synchronous smart cards 
- Exchanging data with supported Smart card (Sending / Receiving)
- Asychron T=0 APDU communication.
- Basic sychron communication 
- ETU calculation from TS byte.
- Support class for SLE4432 / SLE4442 / SLE4441 and SLE4440 compatible sychron smartcards.
  Mostly used for secure data storage.

Open points:
- Error handling not completly implemented.
  No retries if parity error is found.
- Setup of communication parameters from ATR
- T=1 communication not supported (Still possible via "raw" sendBytes(..) / receiveBytes(..))

Releases:

0.0.7rc4:
Merged fix provided by Chris Torr (Thanks for sharing your changes)
- Corrected size of "only" response APDU
- Added support for maxwaits in sendAPDU(...), this will give 
  the user a chance to extend the time the communication stack 
  will wait until marking a APDU communcation as failed.
  
  maxwaits - the number of additional wait cycles to wait 
             Default 0 : no additional wait cycles
                  >= 1 : number of additional (Numbers > 10 
                         should normally not needed)

0.0.7rc3:
- Replaces examples with more intuitive and commented ones.
- Added support class for SLE4432 / SLE4442 / SLE4441 and SLE4440 compatible sychron smartcards.
- Renamed constructor parameters to more intuitive values (API is still the same)
- Added constructor parameter to invert smartcard present switch function (NO vs. NC switch)
  (Defaults to NC behavior)
- Some minor bugfixes

0.0.7rc2:
- Fixed stupid typo in sendAPDU(...). It's not sendADPU(...)
- More stability enhancements to make communication more reliable. 
  Use of guardTime and not hardcoded timeouts.
- small code cleanups

0.0.7rc1:
- Added basic support for T=0 APDU commands.
  - sendAPDU(...)
  - APDU_t type
- Added dumpHEX to SC_DEBUG
- Fixed minor timing problems in receiving area.

0.0.6
- Added calcEDC(..) function for APDU edc calculation. (Can be activated with APDU_SUPPORT. Active per default)
- Fixed problem with sync. cards activation.
- Added SCTest2 example for APDU commands.

0.0.5
- Changed activate() signature to return uint16_t instead of int, which might lead to cast problems
- TS byte is include per default in ATR returned by activate() for async cards.
- Added function to return to old ATR result without TS byte (Default is to include TS byte in ATR).

0.0.4
- General rework to connect smartcard directly to Arduino board.

0.0.3
- Fixed stupid bug leading to none recognition of async response, when parity bit was low ...

0.0.2
- Added support for synchronous cards and auto detection of supported cards type

0.0.1 
- Initial release