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diff --git a/openpicc/application/iso14443_layer2a.h b/openpicc/application/iso14443_layer2a.h
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+++ b/openpicc/application/iso14443_layer2a.h
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+#ifndef ISO14443_LAYER2A_H_
+#define ISO14443_LAYER2A_H_
+
+#include "ssc_picc.h"
+
+/* Callback type for iso14443_receive().
+ * Parameter buffer is being passed a pointer to an SSC Rx buffer structure that this receive happened
+ * on. You might want to pass this into iso14443a_decode_miller().
+ * Parameter in_irq is true if the callback has been called while still in IRQ mode. It must then *NOT*
+ * perform any calls that might upset the IRQ processing. Especially it may not call into FreeRTOS or
+ * any parts of the applications that do.
+ */
+typedef void (*iso14443_receive_callback_t)(ssc_dma_rx_buffer_t *buffer, u_int8_t in_irq);
+
+/* Wait for and receive a frame. Parameters callback and buffer are optional. If you omit them you'll lose
+ * the received frame, obviously.
+ * Parameter callback is a callback function that will be called for each received frame and might
+ * then trigger a response.
+ * Parameter buffer is an output pointer to a pointer to an SSC Rx buffer structure containing the
+ * received frame.
+ * Parameter timeout gives an optional timeout for the receive operation after which the receive will
+ * be aborted. When timeout is 0 the receive will not time out.
+ * This call will block until a frame is received or an exception happens. Obviously it must not be run
+ * from IRQ context.
+ * 
+ * Warning: When you get a buffer from the function then it's state is set to PROCESSING and you must 
+ * FREE it yourself.
+ * 
+ * Return values:
+ * >= 0        Frame received, return value is buffer length (yes, 0 is a valid buffer length)
+ * -ENETDOWN   PLL is not locked or PLL lock lost
+ * -ETIMEDOUT  Receive timed out without receiving anything (usually not regarded an error condition)
+ * -EBUSY      A Tx is currently running or pending; can't receive
+ * -EALREADY   There's already an iso14443_receive() invocation running
+ */
+extern int iso14443_receive(iso14443_receive_callback_t callback, ssc_dma_rx_buffer_t **buffer, unsigned int timeout);
+
+/*
+ * Transmit a frame. Starts transmitting fdt carrier cycles after the end of the received frame.
+ * Parameters buffer and fdt specify the SSC Tx buffer to be sent and the frame delay time in carrier cycles.
+ * When parameter async is set then this call will only schedule the buffer for sending and return immediately,
+ * otherwise the call will block until the buffer has been sent completely, until the specified timeout is reached
+ * or an error occurs.
+ * This function may be run from IRQ context, especially from within the iso14443_receive callback, with the async
+ * parameter set.
+ * 
+ * Note: When your callback calls iso14443_transmit() from IRQ context it must set the async parameter to have transmit
+ * return immediately and then not block within the callback. When the scheduled transmission has not happened by the next
+ * time you call iso14443_receive() it will abort with -EBUSY and you can then either decide to wait for the transmission
+ * to go through, or abort the scheduled transmission with iso14443_tx_abort(). You can check for whether a Tx is currently
+ * pending or running with iso14443_tx_busy().
+ */
+extern int iso14443_transmit(ssc_dma_tx_buffer_t *buffer, unsigned int fdt, u_int8_t async, unsigned int timeout);
+
+extern int iso14443_tx_abort(void);
+extern int iso14443_tx_busy(void);
+
+extern int iso14443_l2a_rx_start(void);
+extern int iso14443_l2a_rx_stop(void);
+
+/*
+ * Wait for the presence of a reader to be detected.
+ * Returns 0 when the PLL is locked.
+ */
+extern int iso14443_wait_for_carrier(unsigned int timeout);
+
+/* Initialize the layer 2 transceiver code.
+ * Parameter enable_fast_receive, when set, will enable special code to guarantee fast response times
+ * for frames shorter than or equal to 56 data bits (bit oriented anticollision frame length). This
+ * generally involves running the callback from an IRQ handler. 
+ */
+extern int iso14443_layer2a_init(u_int8_t enable_fast_receive);
+
+extern u_int8_t iso14443_set_fast_receive(u_int8_t enable_fast_receive);
+extern u_int8_t iso14443_get_fast_receive(void);
+
+#endif /*ISO14443_LAYER2A_H_*/