Add DSLogic capture, signal conversion and DSView decoders

python/logic_analyzer/decoders/transistor_pair.py

@@ -0,0 +1,56 @@
+"""Independent complementary transistor input timing; no ACK/Vstat dependency."""
+import math
+from .gate_timing import InputTimingChecker, format_ns
+
+
+class PairTimingChecker(InputTimingChecker):
+    def __init__(self, samplerate, vin1_active_high=True, vin2_active_high=True,
+                 vin1_mintime_ns=0, vin2_mintime_ns=0,
+                 deadtime_12_ns=0, deadtime_21_ns=0,
+                 vin1_minoff_ns=0, vin2_minoff_ns=0):
+        super().__init__(samplerate, vin1_active_high, vin2_active_high,
+                         vin1_mintime_ns, vin2_mintime_ns)
+        self.deadtime_min = (float(deadtime_12_ns), float(deadtime_21_ns))
+        self.minoff = (float(vin1_minoff_ns), float(vin2_minoff_ns))
+        if any(not math.isfinite(v) or v < 0 for v in self.deadtime_min + self.minoff):
+            raise ValueError('Timing limits must be finite and non-negative')
+        self.last_on = [None, None]
+        self.last_off = [None, None]
+
+    def update(self, sample, vin1, vin2):
+        sample = int(sample)
+        previous = self.levels[:] if self.levels is not None else None
+        events = super().update(sample, vin1, vin2)
+        for event in events:
+            if event['kind'] == 'deadtime':
+                source = event['from_channel'] - 1
+                limit = self.deadtime_min[source]
+                if event['duration_ns'] < limit:
+                    event['kind'] = 'deadtime_fail'
+                    event['text'] = 'FAULT: ' + event['text'] + ' < minimum ' + format_ns(limit)
+                    event['short'] = 'FAULT: deadtime'
+        if previous is None:
+            return events
+        for i in range(2):
+            if previous[i] and not self.levels[i]:
+                self.last_off[i] = sample
+            elif not previous[i] and self.levels[i]:
+                off = self.last_off[i]
+                on = self.last_on[i]
+                if off is not None:
+                    duration = (sample - off) * 1e9 / self.samplerate
+                    failed = duration < self.minoff[i]
+                    events.append(self._event('off_fail' if failed else 'off_time', off, sample,
+                        '%s: Vin%d OFF (minimum %s)' %
+                        ('FAULT' if failed else 'OK', i + 1, format_ns(self.minoff[i])), channel=i+1))
+                if on is not None and off is not None and on < off < sample:
+                    period = sample - on
+                    frequency = self.samplerate / period
+                    duty = 100.0 * (off - on) / period
+                    text = 'Vin%d: period %s, %.3f Hz, duty %.2f%%' % (
+                        i + 1, format_ns(period * 1e9 / self.samplerate), frequency, duty)
+                    events.append(dict(kind='period', start=on, end=sample, text=text,
+                                       short='%.3f Hz / %.2f%%' % (frequency, duty),
+                                       channel=i+1, frequency_hz=frequency, duty_percent=duty))
+                self.last_on[i] = sample
+        return events