X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=bertos%2Fnet%2Fafsk.h;h=b23ba63dde1016e4ed0fb101ddf19066efab4e66;hb=41718ab2098bd5640da265c34f1ecb79a4123d39;hp=2f1a2e08cecf56b99790b2e57aef45f843b71043;hpb=a5d199ea6aed560d3b62c41b73d16d500ba51b99;p=bertos.git

diff --git a/bertos/net/afsk.h b/bertos/net/afsk.h
index 2f1a2e08..b23ba63d 100644
--- a/bertos/net/afsk.h
+++ b/bertos/net/afsk.h
@@ -32,8 +32,7 @@
  *
  * \brief AFSK1200 modem.
  *
- * \version $Id$
- * \author Francesco Sacchi <asterix@develer.com>
+ * \author Francesco Sacchi <batt@develer.com>
  *
  * $WIZ$ module_name = "afsk"
  * $WIZ$ module_configuration = "bertos/cfg/cfg_afsk.h"
@@ -41,28 +40,67 @@
  * $WIZ$ module_hw = "bertos/hw/hw_afsk.h"
  */
 
-#ifndef DRV_AFSK_H
-#define DRV_AFSK_H
+#ifndef NET_AFSK_H
+#define NET_AFSK_H
 
 #include "cfg/cfg_afsk.h"
 #include "hw/hw_afsk.h"
 
-#include <kern/kfile.h>
 #include <cfg/compiler.h>
+
+#include <io/kfile.h>
+
 #include <struct/fifobuf.h>
 
 
-// Demodulator constants
+
+/**
+ * ADC sample rate.
+ * The demodulator filters are designed to work at this frequency.
+ * If you need to change this remember to update afsk_adc_isr().
+ */
 #define SAMPLERATE 9600
+
+/**
+ * Bitrate of the received/transmitted data.
+ * The demodulator filters and decoderes are designed to work at this frequency.
+ * If you need to change this remember to update afsk_adc_isr().
+ */
 #define BITRATE    1200
 
 #define SAMPLEPERBIT (SAMPLERATE / BITRATE)
 
+/**
+ * HDLC (High-Level Data Link Control) context.
+ * Maybe to be moved in a separate HDLC module one day.
+ */
+typedef struct Hdlc
+{
+	uint8_t demod_bits; ///< Bitstream from the demodulator.
+	uint8_t bit_idx;    ///< Current received bit.
+	uint8_t currchar;   ///< Current received character.
+	bool rxstart;       ///< True if an HDLC_FLAG char has been found in the bitstream.
+} Hdlc;
 
+/**
+ * RX FIFO buffer full error.
+ */
+#define AFSK_RXFIFO_OVERRUN BV(0)
+
+/**
+ * AFSK1200 modem context.
+ */
 typedef struct Afsk
 {
+	/** Base "class" */
 	KFile fd;
 
+	/** ADC channel to be used by the demodulator */
+	int adc_ch;
+
+	/** DAC channel to be used by the modulator */
+	int dac_ch;
+
 	/** Current sample of bit for output data. */
 	uint8_t sample_count;
 
@@ -95,29 +133,66 @@ typedef struct Afsk
 	 */
 	int8_t delay_buf[SAMPLEPERBIT / 2 + 1];
 
+	/** FIFO for received data */
 	FIFOBuffer rx_fifo;
+
+	/** FIFO rx buffer */
 	uint8_t rx_buf[CONFIG_AFSK_RX_BUFLEN];
 
+	/** FIFO for transmitted data */
 	FIFOBuffer tx_fifo;
+
+	/** FIFO tx buffer */
 	uint8_t tx_buf[CONFIG_AFSK_TX_BUFLEN];
 
+	/** IIR filter X cells, used to filter sampled data by the demodulator */
 	int16_t iir_x[2];
+
+	/** IIR filter Y cells, used to filter sampled data by the demodulator */
 	int16_t iir_y[2];
 
+	/**
+	 * Bits sampled by the demodulator are here.
+	 * Since ADC samplerate is higher than the bitrate, the bits here are
+	 * SAMPLEPERBIT times the bitrate.
+	 */
 	uint8_t sampled_bits;
-	uint8_t found_bits;
+
+	/**
+	 * Current phase, needed to know when the bitstream at ADC speed
+	 * should be sampled.
+	 */
 	int8_t curr_phase;
 
-	/* True while modem sends data */
+	/** Bits found by the demodulator at the correct bitrate speed. */
+	uint8_t found_bits;
+
+	/** True while modem sends data */
 	volatile bool sending;
 
+	/**
+	 * AFSK modem status.
+	 * If 0 all is ok, otherwise errors are present.
+	 */
+	volatile int status;
 
-	bool hdlc_rxstart;
-	uint8_t hdlc_currchar;
-	uint8_t hdlc_bit_idx;
-	uint8_t hdlc_demod_bits;
+	/** Hdlc context */
+	Hdlc hdlc;
 
+	/**
+	 * Preamble length.
+	 * When the AFSK modem wants to send data, before sending the actual data,
+	 * shifts out preamble_len HDLC_FLAG characters.
+	 * This helps to synchronize the demodulator filters on the receiver side.
+	 */
 	uint16_t preamble_len;
+
+	/**
+	 * Trailer length.
+	 * After sending the actual data, the AFSK shifts out
+	 * trailer_len HDLC_FLAG characters.
+	 * This helps to synchronize the demodulator filters on the receiver side.
+	 */
 	uint16_t trailer_len;
 } Afsk;
 
@@ -129,13 +204,14 @@ INLINE Afsk *AFSK_CAST(KFile *fd)
   return (Afsk *)fd;
 }
 
-void afsk_adc_isr(Afsk *af, int8_t curr_sample);
-void afsk_dac_isr(Afsk *af);
-void afsk_init(Afsk *af);
+
+void afsk_adc_isr(Afsk *af, int8_t sample);
+uint8_t afsk_dac_isr(Afsk *af);
+void afsk_init(Afsk *af, int adc_ch, int dac_ch);
 
 
 /**
- * \name afsk filter type
+ * \name Afsk filter types.
  * $WIZ$ afsk_filter_list = "AFSK_BUTTERWORTH", "AFSK_CHEBYSHEV"
  * \{
  */
@@ -147,4 +223,4 @@ int afsk_testSetup(void);
 int afsk_testRun(void);
 int afsk_testTearDown(void);
 
-#endif
+#endif /* NET_AFSK_H */