[libsigrokdecode.git] / decoders / transitioncounter.py

##
## This file is part of the sigrok project.
##
## Copyright (C) 2010 Uwe Hermann <uwe@hermann-uwe.de>
##
## 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, write to the Free Software
## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
##
import sigrok

lastsample = None
oldbit = None
transitions = None
rising = None
falling = None


def decode(sampledata):
	"""Counts the low->high and high->low transitions in the specified
	   channel(s) of the signal."""
	global lastsample
	global oldbit, transitions, rising, falling

	# TODO: Don't hardcode the number of channels.
	channels = 8	

	# FIXME: Get the data in the correct format in the first place.
	inbuf = [ord(x) for x in sampledata['data']]

	if lastsample == None:
		oldbit = [0] * channels
		transitions = [0] * channels
		rising = [0] * channels
		falling = [0] * channels

		# Initial values.
		lastsample = inbuf[0]
		for i in range(channels):
			oldbit[i] = (lastsample & (1 << i)) >> i
		
	# TODO: Handle LAs with more/less than 8 channels.
	for s in inbuf:
		# Optimization: Skip identical bytes (no transitions).
		if lastsample != s:
			for i in range(channels):
				curbit = (s & (1 << i)) >> i
				# Optimization: Skip identical bits (no transitions).
				if oldbit[i] == curbit:
					continue
				elif (oldbit[i] == 0 and curbit == 1):
					rising[i] += 1
				elif (oldbit[i] == 1 and curbit == 0):
					falling[i] += 1
				oldbit[i] = curbit

			# Total number of transitions is the sum of rising and falling edges.
			for i in range(channels):
				transitions[i] = rising[i] + falling[i]
		
			lastsample = s
			print(transitions)

	sigrok.put(sampledata)

register = {
	'id': 'transitioncounter',
	'name': 'Transition counter',
	'longname': '...',
	'desc': 'Counts rising/falling edges in the signal.',
	'longdesc': '...',
	'author': 'Uwe Hermann',
	'email': 'uwe@hermann-uwe.de',
	'license': 'gplv2+',
	'in': ['logic'],
	'out': ['transitioncounts'],
	'probes': [
		# All probes.
	],
	'options': {
		# No options so far.
	},
	# 'start': start,
	# 'report': report,
}

# Use psyco (if available) as it results in huge performance improvements.
try:
	import psyco
	psyco.bind(decode)
except ImportError:
	pass
Commit	Line	Data
	1	##
	2	## This file is part of the sigrok project.
	3	##
	4	## Copyright (C) 2010 Uwe Hermann <uwe@hermann-uwe.de>
	5	##
	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.
	10	##
	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.
	15	##
	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
	19	##
	20	import sigrok
	21
	22	lastsample = None
	23	oldbit = None
	24	transitions = None
	25	rising = None
	26	falling = None
	27
	28
	29	def decode(sampledata):
	30	"""Counts the low->high and high->low transitions in the specified
	31	channel(s) of the signal."""
	32	global lastsample
	33	global oldbit, transitions, rising, falling
	34
	35	# TODO: Don't hardcode the number of channels.
	36	channels = 8
	37
	38	# FIXME: Get the data in the correct format in the first place.
	39	inbuf = [ord(x) for x in sampledata['data']]
	40
	41	if lastsample == None:
	42	oldbit = [0] * channels
	43	transitions = [0] * channels
	44	rising = [0] * channels
	45	falling = [0] * channels
	46
	47	# Initial values.
	48	lastsample = inbuf[0]
	49	for i in range(channels):
	50	oldbit[i] = (lastsample & (1 << i)) >> i
	51
	52	# TODO: Handle LAs with more/less than 8 channels.
	53	for s in inbuf:
	54	# Optimization: Skip identical bytes (no transitions).
	55	if lastsample != s:
	56	for i in range(channels):
	57	curbit = (s & (1 << i)) >> i
	58	# Optimization: Skip identical bits (no transitions).
	59	if oldbit[i] == curbit:
	60	continue
	61	elif (oldbit[i] == 0 and curbit == 1):
	62	rising[i] += 1
	63	elif (oldbit[i] == 1 and curbit == 0):
	64	falling[i] += 1
	65	oldbit[i] = curbit
	66
	67	# Total number of transitions is the sum of rising and falling edges.
	68	for i in range(channels):
	69	transitions[i] = rising[i] + falling[i]
	70
	71	lastsample = s
	72	print(transitions)
	73
	74	sigrok.put(sampledata)
	75
	76	register = {
	77	'id': 'transitioncounter',
	78	'name': 'Transition counter',
	79	'longname': '...',
	80	'desc': 'Counts rising/falling edges in the signal.',
	81	'longdesc': '...',
	82	'author': 'Uwe Hermann',
	83	'email': 'uwe@hermann-uwe.de',
	84	'license': 'gplv2+',
	85	'in': ['logic'],
	86	'out': ['transitioncounts'],
	87	'probes': [
	88	# All probes.
	89	],
	90	'options': {
	91	# No options so far.
	92	},
	93	# 'start': start,
	94	# 'report': report,
	95	}
	96
	97	# Use psyco (if available) as it results in huge performance improvements.
	98	try:
	99	import psyco
	100	psyco.bind(decode)
	101	except ImportError:
	102	pass
	103