[libsigrokdecode.git] / decoders / pwm / pd.py

##
## This file is part of the libsigrokdecode project.
##
## Copyright (C) 2014 Torsten Duwe <duwe@suse.de>
## Copyright (C) 2014 Sebastien Bourdelin <sebastien.bourdelin@savoirfairelinux.com>
##
## 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 2 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

class Decoder(srd.Decoder):
    api_version = 2
    id = 'pwm'
    name = 'PWM'
    longname = 'Pulse-width modulation'
    desc = 'Analog level encoded in duty cycle percentage.'
    license = 'gplv2+'
    inputs = ['logic']
    outputs = ['pwm']
    channels = (
        {'id': 'data', 'name': 'Data', 'desc': 'Data line'},
    )
    options = (
        {'id': 'polarity', 'desc': 'Polarity', 'default': 'active-high',
            'values': ('active-low', 'active-high')},
    )
    annotations = (
        ('duty-cycle', 'Duty cycle'),
        ('period', 'Period'),
    )
    annotation_rows = (
         ('duty-cycle', 'Duty cycle', (0,)),
         ('period', 'Period', (1,)),
    )
    binary = (
        ('raw', 'RAW file'),
    )

    def __init__(self):
        self.ss_block = self.es_block = None
        self.first_transition = True
        self.first_samplenum = None
        self.start_samplenum = None
        self.end_samplenum = None
        self.oldpin = None
        self.num_cycles = 0
        self.average = 0

    def metadata(self, key, value):
        if key == srd.SRD_CONF_SAMPLERATE:
            self.samplerate = value

    def start(self):
        self.startedge = 0 if self.options['polarity'] == 'active-low' else 1
        self.out_ann = self.register(srd.OUTPUT_ANN)
        self.out_binary = self.register(srd.OUTPUT_BINARY)
        self.out_average = \
            self.register(srd.OUTPUT_META,
                          meta=(float, 'Average', 'PWM base (cycle) frequency'))

    def putx(self, data):
        self.put(self.ss_block, self.es_block, self.out_ann, data)

    def putp(self, period_t):
        # Adjust granularity.
        if period_t == 0 or period_t >= 1:
            period_s = '%.1f s' % (period_t)
        elif period_t <= 1e-12:
            period_s = '%.1f fs' % (period_t * 1e15)
        elif period_t <= 1e-9:
            period_s = '%.1f ps' % (period_t * 1e12)
        elif period_t <= 1e-6:
            period_s = '%.1f ns' % (period_t * 1e9)
        elif period_t <= 1e-3:
            period_s = '%.1f μs' % (period_t * 1e6)
        else:
            period_s = '%.1f ms' % (period_t * 1e3)

        self.put(self.ss_block, self.es_block, self.out_ann, [1, [period_s]])

    def putb(self, data):
        self.put(self.num_cycles, self.num_cycles, self.out_binary, data)

    def decode(self, ss, es, data):

        for (self.samplenum, pins) in data:
            # Ignore identical samples early on (for performance reasons).
            if self.oldpin == pins[0]:
                continue

            # Initialize self.oldpins with the first sample value.
            if self.oldpin is None:
                self.oldpin = pins[0]
                continue

            if self.first_transition:
                # First rising edge
                if self.oldpin != self.startedge:
                    self.first_samplenum = self.samplenum
                    self.start_samplenum = self.samplenum
                    self.first_transition = False
            else:
                if self.oldpin != self.startedge:
                    # Rising edge
                    # We are on a full cycle we can calculate
                    # the period, the duty cycle and its ratio.
                    period = self.samplenum - self.start_samplenum
                    duty = self.end_samplenum - self.start_samplenum
                    ratio = float(duty / period)

                    # This interval starts at this edge.
                    self.ss_block = self.start_samplenum
                    # Store the new rising edge position and the ending
                    # edge interval.
                    self.start_samplenum = self.es_block = self.samplenum

                    # Report the duty cycle in percent.
                    percent = float(ratio * 100)
                    self.putx([0, ['%f%%' % percent]])

                    # Report the duty cycle in the binary output.
                    self.putb([0, bytes([int(ratio * 256)])])

                    # Report the period in units of time.
                    period_t = float(period / self.samplerate)
                    self.putp(period_t)

                    # Update and report the new duty cycle average.
                    self.num_cycles += 1
                    self.average += percent
                    self.put(self.first_samplenum, self.es_block, self.out_average,
                             float(self.average / self.num_cycles))
                else:
                    # Falling edge
                    self.end_samplenum = self.ss_block = self.samplenum

            self.oldpin = pins[0]
Commit	Line	Data
	1	##
	2	## This file is part of the libsigrokdecode project.
	3	##
	4	## Copyright (C) 2014 Torsten Duwe <duwe@suse.de>
	5	## Copyright (C) 2014 Sebastien Bourdelin <sebastien.bourdelin@savoirfairelinux.com>
	6	##
	7	## This program is free software; you can redistribute it and/or modify
	8	## it under the terms of the GNU General Public License as published by
	9	## the Free Software Foundation; either version 2 of the License, or
	10	## (at your option) any later version.
	11	##
	12	## This program is distributed in the hope that it will be useful,
	13	## but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	## GNU General Public License for more details.
	16	##
	17	## You should have received a copy of the GNU General Public License
	18	## along with this program; if not, see <http://www.gnu.org/licenses/>.
	19	##
	20
	21	import sigrokdecode as srd
	22
	23	class Decoder(srd.Decoder):
	24	api_version = 2
	25	id = 'pwm'
	26	name = 'PWM'
	27	longname = 'Pulse-width modulation'
	28	desc = 'Analog level encoded in duty cycle percentage.'
	29	license = 'gplv2+'
	30	inputs = ['logic']
	31	outputs = ['pwm']
	32	channels = (
	33	{'id': 'data', 'name': 'Data', 'desc': 'Data line'},
	34	)
	35	options = (
	36	{'id': 'polarity', 'desc': 'Polarity', 'default': 'active-high',
	37	'values': ('active-low', 'active-high')},
	38	)
	39	annotations = (
	40	('duty-cycle', 'Duty cycle'),
	41	('period', 'Period'),
	42	)
	43	annotation_rows = (
	44	('duty-cycle', 'Duty cycle', (0,)),
	45	('period', 'Period', (1,)),
	46	)
	47	binary = (
	48	('raw', 'RAW file'),
	49	)
	50
	51	def __init__(self):
	52	self.ss_block = self.es_block = None
	53	self.first_transition = True
	54	self.first_samplenum = None
	55	self.start_samplenum = None
	56	self.end_samplenum = None
	57	self.oldpin = None
	58	self.num_cycles = 0
	59	self.average = 0
	60
	61	def metadata(self, key, value):
	62	if key == srd.SRD_CONF_SAMPLERATE:
	63	self.samplerate = value
	64
	65	def start(self):
	66	self.startedge = 0 if self.options['polarity'] == 'active-low' else 1
	67	self.out_ann = self.register(srd.OUTPUT_ANN)
	68	self.out_binary = self.register(srd.OUTPUT_BINARY)
	69	self.out_average = \
	70	self.register(srd.OUTPUT_META,
	71	meta=(float, 'Average', 'PWM base (cycle) frequency'))
	72
	73	def putx(self, data):
	74	self.put(self.ss_block, self.es_block, self.out_ann, data)
	75
	76	def putp(self, period_t):
	77	# Adjust granularity.
	78	if period_t == 0 or period_t >= 1:
	79	period_s = '%.1f s' % (period_t)
	80	elif period_t <= 1e-12:
	81	period_s = '%.1f fs' % (period_t * 1e15)
	82	elif period_t <= 1e-9:
	83	period_s = '%.1f ps' % (period_t * 1e12)
	84	elif period_t <= 1e-6:
	85	period_s = '%.1f ns' % (period_t * 1e9)
	86	elif period_t <= 1e-3:
	87	period_s = '%.1f μs' % (period_t * 1e6)
	88	else:
	89	period_s = '%.1f ms' % (period_t * 1e3)
	90
	91	self.put(self.ss_block, self.es_block, self.out_ann, [1, [period_s]])
	92
	93	def putb(self, data):
	94	self.put(self.num_cycles, self.num_cycles, self.out_binary, data)
	95
	96	def decode(self, ss, es, data):
	97
	98	for (self.samplenum, pins) in data:
	99	# Ignore identical samples early on (for performance reasons).
	100	if self.oldpin == pins[0]:
	101	continue
	102
	103	# Initialize self.oldpins with the first sample value.
	104	if self.oldpin is None:
	105	self.oldpin = pins[0]
	106	continue
	107
	108	if self.first_transition:
	109	# First rising edge
	110	if self.oldpin != self.startedge:
	111	self.first_samplenum = self.samplenum
	112	self.start_samplenum = self.samplenum
	113	self.first_transition = False
	114	else:
	115	if self.oldpin != self.startedge:
	116	# Rising edge
	117	# We are on a full cycle we can calculate
	118	# the period, the duty cycle and its ratio.
	119	period = self.samplenum - self.start_samplenum
	120	duty = self.end_samplenum - self.start_samplenum
	121	ratio = float(duty / period)
	122
	123	# This interval starts at this edge.
	124	self.ss_block = self.start_samplenum
	125	# Store the new rising edge position and the ending
	126	# edge interval.
	127	self.start_samplenum = self.es_block = self.samplenum
	128
	129	# Report the duty cycle in percent.
	130	percent = float(ratio * 100)
	131	self.putx([0, ['%f%%' % percent]])
	132
	133	# Report the duty cycle in the binary output.
	134	self.putb([0, bytes([int(ratio * 256)])])
	135
	136	# Report the period in units of time.
	137	period_t = float(period / self.samplerate)
	138	self.putp(period_t)
	139
	140	# Update and report the new duty cycle average.
	141	self.num_cycles += 1
	142	self.average += percent
	143	self.put(self.first_samplenum, self.es_block, self.out_average,
	144	float(self.average / self.num_cycles))
	145	else:
	146	# Falling edge
	147	self.end_samplenum = self.ss_block = self.samplenum
	148
	149	self.oldpin = pins[0]