Add AD79x0 decoder.

Signed-off-by: Teo Perisanu <Teo.Perisanu@analog.com>

2 files changed, 162 insertions, 0 deletions

diff --git a/decoders/ad79x0/__init__.py b/decoders/ad79x0/__init__.py
new file mode 100644
index 0000000..0e81f17
--- /dev/null
+++ b/decoders/ad79x0/__init__.py
@@ -0,0 +1,25 @@
+##
+## This file is part of the libsigrokdecode project.
+##
+## Copyright (C) 2020 Analog Devices Inc.
+##
+## This program 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 of the License, or
+## (at your option) any later version.
+##
+## This program 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 this program; if not, see <http://www.gnu.org/licenses/>.
+##
+
+'''
+This decoder stacks on top of the 'spi' PD and decodes the
+Analog Devices AD7910/AD7920 protocol.
+'''
+
+from .pd import Decoder
diff --git a/decoders/ad79x0/pd.py b/decoders/ad79x0/pd.py
new file mode 100644
index 0000000..9f3a167
--- /dev/null
+++ b/decoders/ad79x0/pd.py
@@ -0,0 +1,137 @@
+##
+## This file is part of the libsigrokdecode project.
+##
+## Copyright (C) 2020 Analog Devices Inc.
+##
+## This program 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 of the License, or
+## (at your option) any later version.
+##
+## This program 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 this program; if not, see <http://www.gnu.org/licenses/>.
+##
+
+import sigrokdecode as srd
+
+modes = {
+    0: ['Normal Mode', 'Normal', 'Norm', 'N'],
+    1: ['Power Down Mode', 'Power Down', 'PD'],
+    2: ['Power Up Mode', 'Power Up', 'PU'],
+}
+
+input_voltage_format = ['%fV', '%fV', '%.6fV', '%.2fV']
+
+validation = {
+    'invalid': ['Invalid data', 'Invalid', 'N/A'],
+    'incomplete': ['Incomplete conversion', 'Incomplete', 'I'],
+    'complete': ['Complete conversion', 'Complete', 'C'],
+}
+
+class Decoder(srd.Decoder):
+    api_version = 3
+    id = 'ad79x0'
+    name = 'AD79x0'
+    longname = 'Analog Devices AD79x0'
+    desc = 'Analog Devices AD7910/AD7920 12-bit ADC.'
+    license = 'gplv2+'
+    inputs = ['spi']
+    outputs = []
+    tags = ['Display']
+    annotations = (
+        ('mode', 'Mode'),
+        ('data', 'Data'),
+        ('validation', 'Validation'),
+    )
+    annotation_rows = (
+        ('mode', 'Mode', (0,)),
+        ('data', 'Converted data', (1,)),
+        ('data_validation', 'Data validation', (2,)),
+    )
+    options = (
+        {'id': 'ref', 'desc': 'Reference voltage', 'default': 1.5},
+    )
+
+    def __init__(self,):
+        self.reset()
+
+    def reset(self):
+        self.samplerate = 0
+        self.samples_bit = -1
+        self.ss = -1
+        self.start_sample = 0
+        self.previous_state = 0
+        self.data = 0
+
+    def metadata(self, key, value):
+        if key == srd.SRD_CONF_SAMPLERATE:
+            self.samplerate = value
+
+    def start(self):
+        self.out_ann = self.register(srd.OUTPUT_ANN)
+
+    def put_validation(self, pos, msg):
+        self.put(pos[0], pos[1], self.out_ann, [2, validation[msg]])
+
+    def put_data(self, pos, input_voltage):
+        ann = []
+        for format in input_voltage_format:
+            ann.append(format % input_voltage)
+        self.put(pos[0], pos[1], self.out_ann, [1, ann])
+
+    def put_mode(self, pos, msg):
+        self.put(pos[0], pos[1], self.out_ann, [0, modes[msg]])
+
+    def decode(self, ss, es, data):
+        ptype = data[0]
+
+        if ptype == 'CS-CHANGE':
+            cs_old, cs_new = data[1:]
+            if cs_old is not None and cs_old == 0 and cs_new == 1:
+                if self.samples_bit == -1:
+                    return
+                self.data >>= 1
+                nb_bits = (ss - self.ss) // self.samples_bit
+                if nb_bits >= 10:
+                    if self.data == 0xFFF:
+                        self.put_mode([self.start_sample, es], 2)
+                        self.previous_state = 0
+                        self.put_validation([self.start_sample, es], 'invalid')
+                    else:
+                        self.put_mode([self.start_sample, es], 0)
+                        if nb_bits == 16:
+                            self.put_validation([self.start_sample, es], 'complete')
+                        elif nb_bits < 16:
+                            self.put_validation([self.start_sample, es], 'incomplete')
+                        vin = (self.data / ((2**12) - 1)) * self.options['ref']
+                        self.put_data([self.start_sample, es], vin)
+                elif nb_bits < 10:
+                    self.put_mode([self.start_sample, es], 1)
+                    self.previous_state = 1
+                    self.put_validation([self.start_sample, es], 'invalid')
+
+                self.ss = -1
+                self.samples_bit = -1
+                self.data = 0
+            elif cs_old is not None and cs_old == 1 and cs_new == 0:
+                self.start_sample = ss
+                self.samples_bit = -1
+
+        elif ptype == 'BITS':
+            if data[2] is None:
+                return
+            miso = data[2]
+            if self.samples_bit == -1:
+                self.samples_bit = miso[0][2] - miso[0][1]
+
+            if self.ss == -1:
+                self.ss = ss
+
+            for bit in reversed(miso):
+                self.data = self.data | bit[0]
+                self.data <<= 1