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/* -*- c++ -*- */
/*
* Copyright 2001,2004 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 3, 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., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#include "microtune_4937_eval_board.h"
#include "microtune_eval_board_defs.h"
#include "ppio.h"
#include "microtune_4937.h"
static const int TUNER_I2C_ADDR = 0x61;
microtune_4937_eval_board::microtune_4937_eval_board (int which_pp)
: microtune_xxxx_eval_board (which_pp)
{
d_tuner = new microtune_4937 (d_i2c, TUNER_I2C_ADDR);
// disable upstream amplifier
d_ppio->lock ();
int t = d_ppio->read_data ();
t &= ~(UT_DP_TX_ENABLE | UT_DP_TX_SDA | UT_DP_TX_SCL);
t |= UT_DP_TX_AS;
d_ppio->write_data (t);
d_ppio->unlock ();
}
microtune_4937_eval_board::~microtune_4937_eval_board ()
{
// Default action is OK
}
static const float RF_MIN_V = 1.5; // RF AGC control voltages
static const float RF_MAX_V = 4.0;
static const float IF_MIN_V = 2.0; // IF AGC control voltages
static const float IF_MAX_V = 4.0;
static const float MIN_AGC = 0; // bottom of synthetic range
static const float MAX_AGC = 1000; // top of synthetic range
static const float CUTOVER_POINT = 667;
// linear is in the range MIN_AGC to MAX_AGC
static float
linear_to_RF_AGC_voltage (float linear)
{
if (linear >= CUTOVER_POINT)
return RF_MAX_V;
float slope = (RF_MAX_V - RF_MIN_V) / CUTOVER_POINT;
return RF_MIN_V + linear * slope;
}
static float
linear_to_IF_AGC_voltage (float linear)
{
if (linear < CUTOVER_POINT)
return IF_MIN_V;
float slope = (IF_MAX_V - IF_MIN_V) / (MAX_AGC - CUTOVER_POINT);
return IF_MIN_V + (linear - CUTOVER_POINT) * slope;
}
void
microtune_4937_eval_board::set_AGC (float v)
{
if (v < MIN_AGC)
v = MIN_AGC;
if (v > MAX_AGC)
v = MAX_AGC;
float rf_agc_voltage = linear_to_RF_AGC_voltage (v);
float if_agc_voltage = linear_to_IF_AGC_voltage (v);
set_RF_AGC_voltage (rf_agc_voltage);
set_IF_AGC_voltage (if_agc_voltage);
}
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