3 // Copyright 2008,2009 Free Software Foundation, Inc.
5 // This file is part of GNU Radio
7 // GNU Radio is free software; you can redistribute it and/or modify
8 // it under the terms of the GNU General Public License as published by
9 // the Free Software Foundation; either asversion 3, or (at your option)
12 // GNU Radio is distributed in the hope that it will be useful,
13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 // GNU General Public License for more details.
17 // You should have received a copy of the GNU General Public License
18 // along with GNU Radio; see the file COPYING. If not, write to
19 // the Free Software Foundation, Inc., 51 Franklin Street,
20 // Boston, MA 02110-1301, USA.
26 #include <usrp/db_dtt768.h>
27 #include <db_base_impl.h>
32 int C = 0; // Charge Pump Current, no info on how to choose
33 int R = 4; // 125 kHz fref
35 // int ATP = 7; // Disable internal AGC
36 return (0x80 | C<<5 | R);
40 control_byte_5(float freq, int agcmode = 1)
46 else if(freq < 420e6) {
57 else if(freq < 420e6) {
69 int ATC = 0; // AGC time constant = 100ms, 1 = 3S
70 int IFE = 1; // IF AGC amplifier enable
71 int AT = 0; // AGC control, ???
73 return (ATC << 5 | IFE << 4 | AT);
79 int SAS = 1; // SAW Digital mode
80 int AGD = 1; // AGC disable
81 int ADS = 0; // AGC detector into ADC converter
82 int T = 0; // Test mode, undocumented
83 return (SAS << 7 | AGD << 5 | ADS << 4 | T);
86 db_dtt768::db_dtt768(usrp_basic_sptr _usrp, int which)
87 : db_base(_usrp, which)
90 * Control custom DTT76803-based daughterboard.
92 * @param usrp: instance of usrp.source_c
93 * @param which: which side: 0 or 1 corresponding to RX_A or RX_B respectively
109 set_gain((gain_min() + gain_max()) / 2.0);
111 bypass_adc_buffers(false);
114 db_dtt768::~db_dtt768()
119 db_dtt768::gain_min()
125 db_dtt768::gain_max()
131 db_dtt768::gain_db_per_step()
137 db_dtt768::set_gain(float gain)
139 assert(gain>=0 && gain<=115);
141 float rfgain, ifgain, pgagain;
169 db_dtt768::freq_min()
175 db_dtt768::freq_max()
181 db_dtt768::set_freq(double target_freq)
184 * @returns (ok, actual_baseband_freq) where:
185 * ok is True or False and indicates success or failure,
186 * actual_baseband_freq is the RF frequency that corresponds to DC in the IF.
189 freq_result_t ret = {false, 0.0};
191 if(target_freq < freq_min() || target_freq > freq_max()) {
195 double target_lo_freq = target_freq + d_IF; // High side mixing
197 int divisor = (int)(0.5+(target_lo_freq / d_f_ref));
198 double actual_lo_freq = d_f_ref*divisor;
200 if((divisor & ~0x7fff) != 0) { // must be 15-bits or less
204 // build i2c command string
205 std::vector<int> buf(6);
206 buf[0] = (divisor >> 8) & 0xff; // DB1
207 buf[1] = divisor & 0xff; // DB2
208 buf[2] = control_byte_4();
209 buf[3] = control_byte_5(target_freq);
210 buf[4] = control_byte_6();
211 buf[5] = control_byte_7();
213 bool ok = usrp()->write_i2c(d_i2c_addr, int_seq_to_str (buf));
215 d_freq = actual_lo_freq - d_IF;
218 ret.baseband_freq = actual_lo_freq;
225 db_dtt768::is_quadrature()
228 * Return True if this board requires both I & Q analog channels.
230 * This bit of info is useful when setting up the USRP Rx mux register.
237 db_dtt768::spectrum_inverted()
240 * The 43.75 MHz version is inverted
247 db_dtt768::set_bw(float bw)
250 * Choose the SAW filter bandwidth, either 7MHz or 8MHz)
256 return true; // FIXME: propagate set_freq result
260 db_dtt768::_set_rfagc(float gain)
262 assert(gain <= 60 && gain >= 0);
263 // FIXME this has a 0.5V step between gain = 60 and gain = 59.
264 // Why are there two cases instead of a single linear case?
270 voltage = gain/60.0 * 2.25 + 1.25;
273 int dacword = (int)(4096*voltage/1.22/3.3); // 1.22 = opamp gain
275 assert(dacword>=0 && dacword<4096);
276 usrp()->write_aux_dac(d_which, 1, dacword);
280 db_dtt768::_set_ifagc(float gain)
282 assert(gain <= 35 && gain >= 0);
283 float voltage = gain/35.0 * 2.1 + 1.4;
284 int dacword = (int)(4096*voltage/1.22/3.3); // 1.22 = opamp gain
286 assert(dacword>=0 && dacword<4096);
287 usrp()->write_aux_dac(d_which, 0, dacword);
291 db_dtt768::_set_pga(float pga_gain)
293 assert(pga_gain >=0 && pga_gain <=20);
295 usrp()->set_pga (0, pga_gain);
298 usrp()->set_pga (2, pga_gain);