## 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, write to the Free Software
-## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+## along with this program; if not, see <http://www.gnu.org/licenses/>.
##
import sigrokdecode as srd
+from collections import deque
class SamplerateError(Exception):
pass
def normalize_time(t):
if t >= 1.0:
- return '%.3f sec' % t
+ return '%.3f s (%.3f Hz)' % (t, (1/t))
elif t >= 0.001:
- return '%.3f msec' % (t * 1000.0)
+ if 1/t/1000 < 1:
+ return '%.3f ms (%.3f Hz)' % (t * 1000.0, (1/t))
+ else:
+ return '%.3f ms (%.3f kHz)' % (t * 1000.0, (1/t)/1000)
elif t >= 0.000001:
- return '%.3f usec' % (t * 1000.0 * 1000.0)
+ if 1/t/1000/1000 < 1:
+ return '%.3f μs (%.3f kHz)' % (t * 1000.0 * 1000.0, (1/t)/1000)
+ else:
+ return '%.3f μs (%.3f MHz)' % (t * 1000.0 * 1000.0, (1/t)/1000/1000)
elif t >= 0.000000001:
- return '%.3f nsec' % (t * 1000.0 * 1000.0 * 1000.0)
+ if 1/t/1000/1000/1000:
+ return '%.3f ns (%.3f MHz)' % (t * 1000.0 * 1000.0 * 1000.0, (1/t)/1000/1000)
+ else:
+ return '%.3f ns (%.3f GHz)' % (t * 1000.0 * 1000.0 * 1000.0, (1/t)/1000/1000/1000)
else:
return '%f' % t
class Decoder(srd.Decoder):
- api_version = 2
+ api_version = 3
id = 'timing'
name = 'Timing'
- longname = 'Timing calculation'
+ longname = 'Timing calculation with frequency and averaging'
desc = 'Calculate time between edges.'
license = 'gplv2+'
inputs = ['logic']
)
annotations = (
('time', 'Time'),
+ ('average', 'Average'),
)
annotation_rows = (
('time', 'Time', (0,)),
+ ('average', 'Average', (1,)),
+ )
+ options = (
+ { 'id': 'avg_period', 'desc': 'Averaging period', 'default': 100 },
)
- def __init__(self, **kwargs):
+ def __init__(self):
self.samplerate = None
self.oldpin = None
self.last_samplenum = None
+ self.last_n = deque()
+ self.chunks = 0
def metadata(self, key, value):
if key == srd.SRD_CONF_SAMPLERATE:
def start(self):
self.out_ann = self.register(srd.OUTPUT_ANN)
+ self.initial_pins = [0]
- def decode(self, ss, es, data):
+ def decode(self):
if not self.samplerate:
raise SamplerateError('Cannot decode without samplerate.')
-
- for (samplenum, (pin,)) in data:
- # Ignore identical samples early on (for performance reasons).
- if self.oldpin == pin:
- continue
+ while True:
+ pin = self.wait({0: 'e'})
if self.oldpin is None:
self.oldpin = pin
- self.last_samplenum = samplenum
+ self.last_samplenum = self.samplenum
continue
if self.oldpin != pin:
- samples = samplenum - self.last_samplenum
+ samples = self.samplenum - self.last_samplenum
t = samples / self.samplerate
+ self.chunks += 1
+
+ # Don't insert the first chunk into the averaging as it is
+ # not complete probably.
+ if self.last_samplenum is None or self.chunks < 2:
+ # Report the timing normalized.
+ self.put(self.last_samplenum, self.samplenum, self.out_ann,
+ [0, [normalize_time(t)]])
+ else:
+ if t > 0:
+ self.last_n.append(t)
+
+ if len(self.last_n) > self.options['avg_period']:
+ self.last_n.popleft()
- # Report the timing normalized.
- self.put(self.last_samplenum, samplenum, self.out_ann,
- [0, [normalize_time(t)]])
+ # Report the timing normalized.
+ self.put(self.last_samplenum, self.samplenum, self.out_ann,
+ [0, [normalize_time(t)]])
+ self.put(self.last_samplenum, self.samplenum, self.out_ann,
+ [1, [normalize_time(sum(self.last_n) / len(self.last_n))]])
# Store data for next round.
- self.last_samplenum = samplenum
+ self.last_samplenum = self.samplenum
self.oldpin = pin