2 ## This file is part of the libsigrokdecode project.
4 ## Copyright (C) 2012-2015 Uwe Hermann <uwe@hermann-uwe.de>
6 ## This program 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 2 of the License, or
9 ## (at your option) any later version.
11 ## This program 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 this program; if not, write to the Free Software
18 ## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21 import sigrokdecode as srd
30 class Decoder(srd.Decoder):
34 longname = 'Texas Instruments TLC5620'
35 desc = 'Texas Instruments TLC5620 8-bit quad DAC.'
40 {'id': 'clk', 'name': 'CLK', 'desc': 'Serial interface clock'},
41 {'id': 'data', 'name': 'DATA', 'desc': 'Serial interface data'},
44 {'id': 'load', 'name': 'LOAD', 'desc': 'Serial interface load control'},
45 {'id': 'ldac', 'name': 'LDAC', 'desc': 'Load DAC'},
48 ('dac-select', 'DAC select'),
50 ('value', 'DAC value'),
51 ('data-latch', 'Data latch point'),
52 ('ldac-fall', 'LDAC falling edge'),
54 ('reg-write', 'Register write'),
55 ('voltage-update', 'Voltage update'),
56 ('voltage-update-all', 'Voltage update (all DACs)'),
57 ('invalid-cmd', 'Invalid command'),
60 ('bits', 'Bits', (5,)),
61 ('fields', 'Fields', (0, 1, 2)),
62 ('registers', 'Registers', (6, 7)),
63 ('voltage-updates', 'Voltage updates', (8,)),
64 ('events', 'Events', (3, 4)),
65 ('errors', 'Errors', (9,)),
68 def __init__(self, **kwargs):
69 self.oldpins = self.oldclk = self.oldload = self.oldldac = None
71 self.ss_dac_first = None
72 self.ss_dac = self.es_dac = 0
73 self.ss_gain = self.es_gain = 0
74 self.ss_value = self.es_value = 0
75 self.dac_select = self.gain = self.dac_value = None
76 self.dacval = {'A': '?', 'B': '?', 'C': '?', 'D': '?'}
79 self.out_ann = self.register(srd.OUTPUT_ANN)
81 def handle_11bits(self):
82 # Only look at the last 11 bits, the rest is ignored by the TLC5620.
83 if len(self.bits) > 11:
84 self.bits = self.bits[-11:]
86 # If there are less than 11 bits, something is probably wrong.
87 if len(self.bits) < 11:
88 ss, es = self.samplenum, self.samplenum
89 if len(self.bits) >= 2:
91 es = self.bits[-1][1] + (self.bits[1][1] - self.bits[0][1])
92 self.put(ss, es, self.out_ann, [9, ['Command too short']])
96 self.ss_dac = self.bits[0][1]
97 self.es_dac = self.ss_gain = self.bits[2][1]
98 self.es_gain = self.ss_value = self.bits[3][1]
99 self.clock_width = self.es_gain - self.ss_gain
100 self.es_value = self.bits[10][1] + self.clock_width # Guessed.
102 if self.ss_dac_first is None:
103 self.ss_dac_first = self.ss_dac
105 s = ''.join(str(i[0]) for i in self.bits[:2])
106 self.dac_select = s = dacs[int(s, 2)]
107 self.put(self.ss_dac, self.es_dac, self.out_ann,
108 [0, ['DAC select: %s' % s, 'DAC sel: %s' % s,
109 'DAC: %s' % s, 'D: %s' % s, s, s[3]]])
111 self.gain = g = 1 + self.bits[2][0]
112 self.put(self.ss_gain, self.es_gain, self.out_ann,
113 [1, ['Gain: x%d' % g, 'G: x%d' % g, 'x%d' % g]])
115 s = ''.join(str(i[0]) for i in self.bits[3:])
116 self.dac_value = v = int(s, 2)
117 self.put(self.ss_value, self.es_value, self.out_ann,
118 [2, ['DAC value: %d' % v, 'Value: %d' % v, 'Val: %d' % v,
119 'V: %d' % v, '%d' % v]])
121 # Emit an annotation for each bit.
122 for i in range(1, 11):
123 self.put(self.bits[i - 1][1], self.bits[i][1], self.out_ann,
124 [5, [str(self.bits[i - 1][0])]])
125 self.put(self.bits[10][1], self.bits[10][1] + self.clock_width,
126 self.out_ann, [5, [str(self.bits[10][0])]])
132 def handle_falling_edge_load(self):
133 if not self.handle_11bits():
135 s, v, g = self.dac_select, self.dac_value, self.gain
136 self.put(self.samplenum, self.samplenum, self.out_ann,
137 [3, ['Falling edge on LOAD', 'LOAD fall', 'F']])
139 # If LDAC is low, the voltage is set immediately.
140 self.put(self.ss_dac, self.es_value, self.out_ann,
141 [7, ['Setting %s voltage to %d (x%d gain)' % (s, v, g),
142 '%s=%d (x%d gain)' % (s, v, g)]])
144 # If LDAC is high, the voltage is not set immediately, but rather
145 # stored in a register. When LDAC goes low all four DAC voltages
146 # (DAC A/B/C/D) will be set at the same time.
147 self.put(self.ss_dac, self.es_value, self.out_ann,
148 [6, ['Setting %s register value to %d (x%d gain)' % \
149 (s, v, g), '%s=%d (x%d gain)' % (s, v, g)]])
150 # Save the last value the respective DAC was set to.
151 self.dacval[self.dac_select[-1]] = str(self.dac_value)
153 def handle_falling_edge_ldac(self):
154 self.put(self.samplenum, self.samplenum, self.out_ann,
155 [4, ['Falling edge on LDAC', 'LDAC fall', 'LDAC', 'L']])
157 # Don't emit any annotations if we didn't see any register writes.
158 if self.ss_dac_first is None:
161 s = ''.join(['DAC%s=%s ' % (d, self.dacval[d]) for d in 'ABCD']).strip()
162 self.put(self.ss_dac_first, self.samplenum, self.out_ann,
163 [8, ['Updating voltages: %s' % s, s, s.replace('DAC', '')]])
164 self.ss_dac_first = None
166 def handle_new_dac_bit(self):
167 self.bits.append([self.datapin, self.samplenum])
169 def decode(self, ss, es, data):
170 for (self.samplenum, pins) in data:
172 # Ignore identical samples early on (for performance reasons).
173 if self.oldpins == pins:
175 self.oldpins, (clk, self.datapin, load, ldac) = pins, pins
178 # DATA is shifted in the DAC on the falling CLK edge (MSB-first).
179 # A falling edge of LOAD will latch the data.
181 if self.oldload == 1 and load == 0:
182 self.handle_falling_edge_load()
183 if self.oldldac == 1 and ldac == 0:
184 self.handle_falling_edge_ldac()
185 if self.oldclk == 1 and clk == 0:
186 self.handle_new_dac_bit()