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#ifndef ISO14443_LAYER3A_H_
#define ISO14443_LAYER3A_H_
extern void iso14443_layer3a_state_machine (void *pvParameters);
enum ISO14443_STATES {
STARTING_UP, /* Hardware has not been initialized, initialize hardware, go to power-off */
POWERED_OFF, /* Card not in field, wait for PLL lock */
IDLE, /* Card in field and powered, wait for REQA or WUPA */
READY, /* Perform anticollision, wait for select */
ACTIVE, /* Selected */
HALT, /* Card halted and powered, wait for WUPA */
READY_STAR, /* Perform anticollision, wait for select */
ACTIVE_STAR, /* Selected */
ERROR, /* Some unrecoverable error has occured */
};
/******************** RX ************************************/
/* measured TF->FIQ->SSC TX start delay (~3.480us) in carrier cycles */
#define TF_FIQ_SSC_DELAY 47
//#define TF_FIQ_SSC_DELAY 40
#define FALLING_EDGE_DETECTION_DELAY 12
extern volatile int fdt_offset;
/* standard derived magic values */
#define ISO14443A_FDT_SLOTLEN 128
#define ISO14443A_FDT_OFFSET_1 84
#define ISO14443A_FDT_OFFSET_0 20
#define ISO14443A_FDT_SHORT_1 (ISO14443A_FDT_SLOTLEN*9 + ISO14443A_FDT_OFFSET_1 -FALLING_EDGE_DETECTION_DELAY +fdt_offset -TF_FIQ_SSC_DELAY)
#define ISO14443A_FDT_SHORT_0 (ISO14443A_FDT_SLOTLEN*9 + ISO14443A_FDT_OFFSET_0 -FALLING_EDGE_DETECTION_DELAY +fdt_offset -TF_FIQ_SSC_DELAY)
#ifdef FOUR_TIMES_OVERSAMPLING
/* definitions for four-times oversampling */
/* Sample values for the REQA and WUPA short frames */
#define REQA 0x10410441
#define WUPA 0x04041041
/* Start of frame sample for SSC compare 0 */
#define ISO14443A_SOF_SAMPLE 0x01
#define ISO14443A_SOF_LEN 4
/* Length in samples of a short frame */
#define ISO14443A_SHORT_LEN 32
/* This is wrong: a short frame is 1 start bit, 7 data bits, 1 stop bit
* followed by no modulation for one bit period. The start bit is 'eaten' in
* SSC Compare 0, but the remaining 7+1+1 bit durations must be sampled and
* compared. At four times oversampling this would be 9*4=36 samples, which is
* more than one SSC transfer. You'd have to use two transfers of 18 samples
* each and modify the comparison code accordingly.
* Since four times oversampling doesn't work reliably anyway (every second
* sample is near an edge and might sample 0 or 1) this doesn't matter for now.*/
#error Four times oversampling is broken, see comments in code
#else
/* definitions for two-times oversampling */
#define REQA 0x4929
#define WUPA 0x2249
#define ISO14443A_SOF_SAMPLE 0x01
#define ISO14443A_SOF_LEN 2
#define ISO14443A_SHORT_LEN 18
#endif
/* A short frame should be received in one single SSC transfer */
#if (ISO14443A_SHORT_LEN <= 8)
/* SSC transfer size in bits */
#define ISO14443A_SHORT_TRANSFER_SIZE 8
#define ISO14443A_SHORT_TYPE u_int8_t
#elif (ISO14443A_SHORT_LEN <= 16)
#define ISO14443A_SHORT_TRANSFER_SIZE 16
#define ISO14443A_SHORT_TYPE u_int16_t
#elif (ISO14443A_SHORT_LEN <= 32)
#define ISO14443A_SHORT_TRANSFER_SIZE 32
#define ISO14443A_SHORT_TYPE u_int32_t
#else
#error ISO14443A_SHORT_LEN defined too big
#endif
/******************** TX ************************************/
/* in bytes, not counting parity */
#define MAXIMUM_FRAME_SIZE 256
typedef struct {
enum { TYPE_A, TYPE_B } type;
union {
struct {
enum { SHORT_FRAME, STANDARD_FRAME, AC_FRAME } format;
enum { PARITY, /* Calculate parity on the fly, ignore the parity field below */
GIVEN_PARITY, /* Use the parity bits from the parity field below */
NO_PARITY, /* Don't send any parity */
} parity;
} a;
} parameters;
u_int32_t numbytes;
u_int8_t numbits, bit_offset;
u_int8_t data[MAXIMUM_FRAME_SIZE];
u_int8_t parity[MAXIMUM_FRAME_SIZE]; /* Only the LSB of each byte is used */
} iso14443_frame;
extern const iso14443_frame ATQA_FRAME;
#endif /*ISO14443_LAYER3A_H_*/
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