2 # Copyright 2005 Free Software Foundation, Inc.
4 # This file is part of GNU Radio
6 # GNU Radio is free software; you can redistribute it and/or modify
7 # it under the terms of the GNU General Public License as published by
8 # the Free Software Foundation; either version 3, or (at your option)
11 # GNU Radio is distributed in the hope that it will be useful,
12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 # GNU General Public License for more details.
16 # You should have received a copy of the GNU General Public License
17 # along with GNU Radio; see the file COPYING. If not, write to
18 # the Free Software Foundation, Inc., 51 Franklin Street,
19 # Boston, MA 02110-1301, USA.
25 from usrpm import usrp_dbid
27 import db_instantiator
29 def int_seq_to_str(seq):
30 """convert a sequence of integers into a string"""
31 return ''.join (map (chr, seq))
33 def str_to_int_seq(str):
34 """convert a string to a list of integers"""
38 C = 0 # Charge Pump Current, no info on how to choose
42 ATP = 7 # Disable internal AGC
43 return 0x80 | C<<5 | R
45 def control_byte_5(freq,agcmode = 1):
62 ATC = 0 # AGC time constant = 100ms, 1 = 3S
63 IFE = 1 # IF AGC amplifier enable
64 AT = 0 # AGC control, ???
66 return ATC << 5 | IFE << 4 | AT
69 SAS = 1 # SAW Digital mode
71 ADS = 0 # AGC detector into ADC converter
72 T = 0 # Test mode, undocumented
73 return SAS << 7 | AGD << 5 | ADS << 4 | T
75 class db_dtt768(db_base.db_base):
76 def __init__(self, usrp, which):
78 Control custom DTT76803-based daughterboard.
80 @param usrp: instance of usrp.source_c
81 @param which: which side: 0 or 1 corresponding to RX_A or RX_B respectively
85 db_base.db_base.__init__(self, usrp, which)
87 self._i2c_addr = (0x60, 0x62)[which]
91 self._inverted = False
93 g = self.gain_range() # initialize gain
94 self.set_gain(float(g[0]+g[1]) / 2)
96 self.bypass_adc_buffers(False)
99 def _set_rfagc(self,gain):
100 assert gain <= 60 and gain >= 0
101 # FIXME this has a 0.5V step between gain = 60 and gain = 59.
102 # Why are there two cases instead of a single linear case?
106 voltage = gain/60.0 * 2.25 + 1.25
107 dacword = int(4096*voltage/1.22/3.3) # 1.22 = opamp gain
109 assert dacword>=0 and dacword<4096
110 self._u.write_aux_dac(self._which, 1, dacword)
112 def _set_ifagc(self,gain):
113 assert gain <= 35 and gain >= 0
114 voltage = gain/35.0 * 2.1 + 1.4
115 dacword = int(4096*voltage/1.22/3.3) # 1.22 = opamp gain
117 assert dacword>=0 and dacword<4096
118 self._u.write_aux_dac(self._which, 0, dacword)
120 def _set_pga(self,pga_gain):
121 assert pga_gain >=0 and pga_gain <=20
122 if(self._which == 0):
123 self._u.set_pga (0, pga_gain)
125 self._u.set_pga (2, pga_gain)
127 def gain_range(self):
130 def set_gain(self,gain):
131 assert gain>=0 and gain<=115
145 self._set_rfagc(rfgain)
146 self._set_ifagc(ifgain)
147 self._set_pga(pgagain)
149 def freq_range(self):
150 return (44e6, 900e6, 10e3)
152 def set_freq(self, target_freq):
154 @returns (ok, actual_baseband_freq) where:
155 ok is True or False and indicates success or failure,
156 actual_baseband_freq is the RF frequency that corresponds to DC in the IF.
158 r = self.freq_range()
159 if target_freq < r[0] or target_freq > r[1]:
162 target_lo_freq = target_freq + self._IF; # High side mixing
164 divisor = int(0.5+(target_lo_freq / self.f_ref))
165 actual_lo_freq = self.f_ref*divisor
167 if (divisor & ~0x7fff) != 0: # must be 15-bits or less
170 # build i2c command string
172 buf[0] = (divisor >> 8) & 0xff # DB1
173 buf[1] = divisor & 0xff # DB2
174 buf[2] = control_byte_4()
175 buf[3] = control_byte_5(target_freq)
176 buf[4] = control_byte_6()
177 buf[5] = control_byte_7()
179 ok = self._u.write_i2c(self._i2c_addr, int_seq_to_str (buf))
181 self.freq = actual_lo_freq - self._IF
183 return (ok, actual_lo_freq)
185 def is_quadrature(self):
187 Return True if this board requires both I & Q analog channels.
189 This bit of info is useful when setting up the USRP Rx mux register.
193 def spectrum_inverted(self):
195 The 43.75 MHz version is inverted
197 return self._inverted
199 # hook this daughterboard class into the auto-instantiation framework
202 db_instantiator.add(usrp_dbid.DTT768,
203 lambda usrp, which : (db_dtt768(usrp, which),))