1 files changed, 146 insertions, 0 deletions
diff --git a/gnuradio-core/src/lib/io/microtune_4937.cc b/gnuradio-core/src/lib/io/microtune_4937.cc
new file mode 100644
index 0000000000..c05f63c113
--- /dev/null
+++ b/gnuradio-core/src/lib/io/microtune_4937.cc
@@ -0,0 +1,146 @@
+/* -*- c++-*- */
+/*
+ * Copyright 2001,2003 Free Software Foundation, Inc.
+ * 
+ * This file is part of GNU Radio
+ * 
+ * GNU Radio is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ * 
+ * GNU Radio is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Radio; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#include "microtune_4937.h"
+#include <stdlib.h>
+#include <stdio.h>
+#include <i2c.h>
+
+static const double first_IF = 43.75e6;
+
+// The tuner internally has 3 bands: VHF Low, VHF High & UHF.
+// These are the recommened boundaries
+static const double VHF_High_takeover = 158e6;
+static const double UHF_takeover = 464e6;
+
+
+static unsigned char
+control_byte_1 (bool fast_tuning_p, int reference_divisor)
+{
+  int c = 0x88;
+
+  if (fast_tuning_p)
+    c |= 0x40;
+
+  switch (reference_divisor){
+  case 512:
+    c |= 0x3 << 1;	break;
+  case 640:
+    c |= 0x0 << 1;	break;
+  case 1024:
+    c |= 0x1 << 1;	break;
+  default:
+    abort ();
+  }
+  return c;
+}
+
+static unsigned char
+control_byte_2 (double target_freq, bool shutdown_tx_PGA)
+{
+  int	c;
+
+  if (target_freq < VHF_High_takeover)	// VHF low
+    c = 0xa0;
+  else if (target_freq < UHF_takeover)	// VHF high
+    c = 0x90;
+  else					// UHF
+    c = 0x30;
+
+  if (shutdown_tx_PGA)
+    c |= 0x08;
+
+  return c;
+}
+
+microtune_4937::microtune_4937 (i2c_sptr i2c, int i2c_addr)
+{
+  d_i2c = i2c;
+  d_i2c_addr = i2c_addr;
+  d_reference_divider = 640;
+  d_fast_tuning_p  = false;
+}
+
+microtune_4937::~microtune_4937 ()
+{
+  // nop
+}
+
+/*!
+ * \brief select RF frequency to be tuned to output frequency.
+ * \p target_freq is the requested frequency in Hz, \p actual_freq
+ * is set to the actual frequency tuned.  It takes about 100 ms
+ * for the PLL to settle.
+ *
+ * \returns true iff sucessful.
+ */
+bool
+microtune_4937::set_RF_freq (double target_freq, double *p_actual_freq)
+{
+  unsigned char buf[4];
+
+  double target_f_osc = target_freq + first_IF;
+  
+  double f_ref = 4e6 / d_reference_divider;
+
+  // f_osc = f_ref * 8 * divisor
+  // divisor = f_osc / (f_ref * 8)
+
+  int divisor = (int) ((target_f_osc + (f_ref * 4)) / (f_ref * 8));
+  double actual_freq = (f_ref * 8 * divisor) - first_IF;
+  if (p_actual_freq != 0)
+    *p_actual_freq = actual_freq;
+
+  if ((divisor & ~0x7fff) != 0)	// 15 bit divisor
+    return false;
+
+  buf[0] = (divisor >> 8) & 0xff;	// DB1
+  buf[1] = divisor & 0xff;		// DB2
+  buf[2] = control_byte_1 (d_fast_tuning_p, d_reference_divider);
+  buf[3] = control_byte_2 (target_freq, true);
+
+#if 0
+  printf ("set_RF_freq: target: %g MHz actual: %g MHz %02x %02x %02x %02x\n",
+	  target_freq/1e6, actual_freq/1e6, buf[0], buf[1], buf[2], buf[3]);
+#endif
+
+  return d_i2c->write (d_i2c_addr, buf, 4);
+}
+
+/*!
+ * \returns true iff PLL is locked
+ */
+bool 
+microtune_4937::pll_locked_p ()
+{
+  // FIXME
+  return true;
+}
+
+/*!
+ * \returns the output frequency of the tuner in Hz.
+ */
+double
+microtune_4937::get_output_freq ()
+{
+  return 5.75e6;	// 3x7702
+}