3 // Copyright 2008 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.
22 #include <db_dtt768.h>
23 #include <db_base_impl.h>
28 int C = 0; // Charge Pump Current, no info on how to choose
29 int R = 4; // 125 kHz fref
31 // int ATP = 7; // Disable internal AGC
32 return (0x80 | C<<5 | R);
36 control_byte_5(float freq, int agcmode = 1)
42 else if(freq < 420e6) {
53 else if(freq < 420e6) {
65 int ATC = 0; // AGC time constant = 100ms, 1 = 3S
66 int IFE = 1; // IF AGC amplifier enable
67 int AT = 0; // AGC control, ???
69 return (ATC << 5 | IFE << 4 | AT);
75 int SAS = 1; // SAW Digital mode
76 int AGD = 1; // AGC disable
77 int ADS = 0; // AGC detector into ADC converter
78 int T = 0; // Test mode, undocumented
79 return (SAS << 7 | AGD << 5 | ADS << 4 | T);
82 db_dtt768::db_dtt768(usrp_basic_sptr _usrp, int which)
83 : db_base(_usrp, which)
86 * Control custom DTT76803-based daughterboard.
88 * @param usrp: instance of usrp.source_c
89 * @param which: which side: 0 or 1 corresponding to RX_A or RX_B respectively
105 set_gain((gain_min() + gain_max()) / 2.0);
107 bypass_adc_buffers(false);
110 db_dtt768::~db_dtt768()
115 db_dtt768::gain_min()
121 db_dtt768::gain_max()
127 db_dtt768::gain_db_per_step()
133 db_dtt768::set_gain(float gain)
135 assert(gain>=0 && gain<=115);
137 float rfgain, ifgain, pgagain;
165 db_dtt768::freq_min()
171 db_dtt768::freq_max()
177 db_dtt768::set_freq(double target_freq)
180 * @returns (ok, actual_baseband_freq) where:
181 * ok is True or False and indicates success or failure,
182 * actual_baseband_freq is the RF frequency that corresponds to DC in the IF.
185 freq_result_t ret = {false, 0.0};
187 if(target_freq < freq_min() || target_freq > freq_max()) {
191 double target_lo_freq = target_freq + d_IF; // High side mixing
193 int divisor = (int)(0.5+(target_lo_freq / d_f_ref));
194 double actual_lo_freq = d_f_ref*divisor;
196 if((divisor & ~0x7fff) != 0) { // must be 15-bits or less
200 // build i2c command string
201 std::vector<int> buf(6);
202 buf[0] = (divisor >> 8) & 0xff; // DB1
203 buf[1] = divisor & 0xff; // DB2
204 buf[2] = control_byte_4();
205 buf[3] = control_byte_5(target_freq);
206 buf[4] = control_byte_6();
207 buf[5] = control_byte_7();
209 bool ok = usrp()->write_i2c(d_i2c_addr, int_seq_to_str (buf));
211 d_freq = actual_lo_freq - d_IF;
214 ret.baseband_freq = actual_lo_freq;
221 db_dtt768::is_quadrature()
224 * Return True if this board requires both I & Q analog channels.
226 * This bit of info is useful when setting up the USRP Rx mux register.
233 db_dtt768::spectrum_inverted()
236 * The 43.75 MHz version is inverted
243 db_dtt768::set_bw(float bw)
246 * Choose the SAW filter bandwidth, either 7MHz or 8MHz)
252 return true; // FIXME: propagate set_freq result
256 db_dtt768::_set_rfagc(float gain)
258 assert(gain <= 60 && gain >= 0);
259 // FIXME this has a 0.5V step between gain = 60 and gain = 59.
260 // Why are there two cases instead of a single linear case?
266 voltage = gain/60.0 * 2.25 + 1.25;
269 int dacword = (int)(4096*voltage/1.22/3.3); // 1.22 = opamp gain
271 assert(dacword>=0 && dacword<4096);
272 usrp()->write_aux_dac(d_which, 1, dacword);
276 db_dtt768::_set_ifagc(float gain)
278 assert(gain <= 35 && gain >= 0);
279 float voltage = gain/35.0 * 2.1 + 1.4;
280 int dacword = (int)(4096*voltage/1.22/3.3); // 1.22 = opamp gain
282 assert(dacword>=0 && dacword<4096);
283 usrp()->write_aux_dac(d_which, 0, dacword);
287 db_dtt768::_set_pga(float pga_gain)
289 assert(pga_gain >=0 && pga_gain <=20);
291 usrp()->set_pga (0, pga_gain);
294 usrp()->set_pga (2, pga_gain);