## 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 common.srdhelper import bitpack
from .lists import *
+import sigrokdecode as srd
+
+# Concentrate all timing constraints of the IR protocol here in a single
+# location at the top of the source, to raise awareness and to simplify
+# review and adjustment. The tolerance is an arbitrary choice, available
+# literature does not mention any. The inter-frame timeout is not a part
+# of the protocol, but an implementation detail of this sigrok decoder.
+_TIME_TOL = 8 # tolerance, in percent
+_TIME_IDLE = 20.0 # inter-frame timeout, in ms
+_TIME_LC = 13.5 # leader code, in ms
+_TIME_RC = 11.25 # repeat code, in ms
+_TIME_ONE = 2.25 # one data bit, in ms
+_TIME_ZERO = 1.125 # zero data bit, in ms
+_TIME_STOP = 0.562 # stop bit, in ms
+
+class SamplerateError(Exception):
+ pass
+
+class Pin:
+ IR, = range(1)
+
+class Ann:
+ BIT, AGC, LONG_PAUSE, SHORT_PAUSE, STOP_BIT, \
+ LEADER_CODE, ADDR, ADDR_INV, CMD, CMD_INV, REPEAT_CODE, \
+ REMOTE, WARN = range(13)
class Decoder(srd.Decoder):
- api_version = 1
+ api_version = 3
id = 'ir_nec'
name = 'IR NEC'
longname = 'IR NEC'
desc = 'NEC infrared remote control protocol.'
license = 'gplv2+'
inputs = ['logic']
- outputs = ['ir_nec']
- probes = (
+ outputs = []
+ tags = ['IR']
+ channels = (
{'id': 'ir', 'name': 'IR', 'desc': 'Data line'},
)
options = (
{'id': 'polarity', 'desc': 'Polarity', 'default': 'active-low',
- 'values': ('active-low', 'active-high')},
+ 'values': ('auto', 'active-low', 'active-high')},
+ {'id': 'cd_freq', 'desc': 'Carrier Frequency', 'default': 0},
+ {'id': 'extended', 'desc': 'Extended NEC Protocol',
+ 'default': 'no', 'values': ('yes', 'no')},
)
annotations = (
('bit', 'Bit'),
('cmd-inv', 'Command#'),
('repeat-code', 'Repeat code'),
('remote', 'Remote'),
- ('warnings', 'Warnings'),
+ ('warning', 'Warning'),
)
annotation_rows = (
- ('bits', 'Bits', (0, 1, 2, 3, 4)),
- ('fields', 'Fields', (5, 6, 7, 8, 9, 10)),
- ('remote', 'Remote', (11,)),
- ('warnings', 'Warnings', (12,)),
+ ('bits', 'Bits', (Ann.BIT, Ann.AGC, Ann.LONG_PAUSE, Ann.SHORT_PAUSE, Ann.STOP_BIT)),
+ ('fields', 'Fields', (Ann.LEADER_CODE, Ann.ADDR, Ann.ADDR_INV, Ann.CMD, Ann.CMD_INV, Ann.REPEAT_CODE)),
+ ('remote-vals', 'Remote', (Ann.REMOTE,)),
+ ('warnings', 'Warnings', (Ann.WARN,)),
)
def putx(self, data):
def putb(self, data):
self.put(self.ss_bit, self.samplenum, self.out_ann, data)
- def putd(self, data):
+ def putd(self, data, bit_count):
name = self.state.title()
- d = {'ADDRESS': 6, 'ADDRESS#': 7, 'COMMAND': 8, 'COMMAND#': 9}
+ d = {'ADDRESS': Ann.ADDR, 'ADDRESS#': Ann.ADDR_INV,
+ 'COMMAND': Ann.CMD, 'COMMAND#': Ann.CMD_INV}
s = {'ADDRESS': ['ADDR', 'A'], 'ADDRESS#': ['ADDR#', 'A#'],
'COMMAND': ['CMD', 'C'], 'COMMAND#': ['CMD#', 'C#']}
- self.putx([d[self.state], ['%s: 0x%02X' % (name, data),
- '%s: 0x%02X' % (s[self.state][0], data),
- '%s: 0x%02X' % (s[self.state][1], data), s[self.state][1]]])
+ fmt = '{{}}: 0x{{:0{}X}}'.format(bit_count // 4)
+ self.putx([d[self.state], [
+ fmt.format(name, data),
+ fmt.format(s[self.state][0], data),
+ fmt.format(s[self.state][1], data),
+ s[self.state][1],
+ ]])
def putstop(self, ss):
self.put(ss, ss + self.stop, self.out_ann,
- [4, ['Stop bit', 'Stop', 'St', 'S']])
+ [Ann.STOP_BIT, ['Stop bit', 'Stop', 'St', 'S']])
def putpause(self, p):
self.put(self.ss_start, self.ss_other_edge, self.out_ann,
- [1, ['AGC pulse', 'AGC', 'A']])
- idx = 2 if p == 'Long' else 3
- self.put(self.ss_other_edge, self.samplenum, self.out_ann,
- [idx, [p + ' pause', '%s-pause' % p[0], '%sP' % p[0], 'P']])
+ [Ann.AGC, ['AGC pulse', 'AGC', 'A']])
+ idx = Ann.LONG_PAUSE if p == 'Long' else Ann.SHORT_PAUSE
+ self.put(self.ss_other_edge, self.samplenum, self.out_ann, [idx, [
+ '{} pause'.format(p),
+ '{}-pause'.format(p[0]),
+ '{}P'.format(p[0]),
+ 'P',
+ ]])
def putremote(self):
dev = address.get(self.addr, 'Unknown device')
- buttons = command.get(self.addr, None)
- if buttons is None:
- btn = ['Unknown', 'Unk']
- else:
- btn = buttons.get(self.cmd, ['Unknown', 'Unk'])
- self.put(self.ss_remote, self.ss_bit + self.stop, self.out_ann,
- [11, ['%s: %s' % (dev, btn[0]), '%s: %s' % (dev, btn[1]),
- '%s' % btn[1]]])
+ buttons = command.get(self.addr, {})
+ btn = buttons.get(self.cmd, ['Unknown', 'Unk'])
+ self.put(self.ss_remote, self.ss_bit + self.stop, self.out_ann, [Ann.REMOTE, [
+ '{}: {}'.format(dev, btn[0]),
+ '{}: {}'.format(dev, btn[1]),
+ '{}'.format(btn[1]),
+ ]])
+
+ def __init__(self):
+ self.reset()
- def __init__(self, **kwargs):
+ def reset(self):
self.state = 'IDLE'
self.ss_bit = self.ss_start = self.ss_other_edge = self.ss_remote = 0
- self.data = self.count = self.active = self.old_ir = None
+ self.data = []
self.addr = self.cmd = None
def start(self):
- # self.out_python = self.register(srd.OUTPUT_PYTHON)
self.out_ann = self.register(srd.OUTPUT_ANN)
- self.active = 0 if self.options['polarity'] == 'active-low' else 1
- self.old_ir = 1 if self.active == 0 else 0
def metadata(self, key, value):
if key == srd.SRD_CONF_SAMPLERATE:
self.samplerate = value
- self.margin = int(self.samplerate * 0.0001) - 1 # 0.1ms
- self.lc = int(self.samplerate * 0.0135) - 1 # 13.5ms
- self.rc = int(self.samplerate * 0.01125) - 1 # 11.25ms
- self.dazero = int(self.samplerate * 0.001125) - 1 # 1.125ms
- self.daone = int(self.samplerate * 0.00225) - 1 # 2.25ms
- self.stop = int(self.samplerate * 0.000652) - 1 # 0.652ms
+
+ def calc_rate(self):
+ self.tolerance = _TIME_TOL / 100
+ self.lc = int(self.samplerate * _TIME_LC / 1000) - 1
+ self.rc = int(self.samplerate * _TIME_RC / 1000) - 1
+ self.dazero = int(self.samplerate * _TIME_ZERO / 1000) - 1
+ self.daone = int(self.samplerate * _TIME_ONE / 1000) - 1
+ self.stop = int(self.samplerate * _TIME_STOP / 1000) - 1
+ self.idle_to = int(self.samplerate * _TIME_IDLE / 1000) - 1
+
+ def compare_with_tolerance(self, measured, base):
+ return (measured >= base * (1 - self.tolerance)
+ and measured <= base * (1 + self.tolerance))
def handle_bit(self, tick):
ret = None
- if tick in range(self.dazero - self.margin, self.dazero + self.margin):
+ if self.compare_with_tolerance(tick, self.dazero):
ret = 0
- elif tick in range(self.daone - self.margin, self.daone + self.margin):
+ elif self.compare_with_tolerance(tick, self.daone):
ret = 1
if ret in (0, 1):
- self.putb([0, ['%d' % ret]])
- self.data |= (ret << self.count) # LSB-first
- self.count = self.count + 1
+ self.putb([Ann.BIT, ['{:d}'.format(ret)]])
+ self.data.append(ret)
self.ss_bit = self.samplenum
- def data_ok(self):
- ret, name = (self.data >> 8) & (self.data & 0xff), self.state.title()
- if self.count == 8:
+ def data_ok(self, check, want_len):
+ name = self.state.title()
+ normal, inverted = bitpack(self.data[:8]), bitpack(self.data[8:])
+ valid = (normal ^ inverted) == 0xff
+ show = inverted if self.state.endswith('#') else normal
+ is_ext_addr = self.is_extended and self.state == 'ADDRESS'
+ if is_ext_addr:
+ normal = bitpack(self.data)
+ show = normal
+ valid = True
+ if len(self.data) == want_len:
if self.state == 'ADDRESS':
- self.addr = self.data
+ self.addr = normal
if self.state == 'COMMAND':
- self.cmd = self.data
- self.putd(self.data)
+ self.cmd = normal
+ self.putd(show, want_len)
self.ss_start = self.samplenum
+ if is_ext_addr:
+ self.data = []
+ self.ss_bit = self.ss_start = self.samplenum
return True
- if ret == 0:
- self.putd(self.data >> 8)
- else:
- self.putx([12, ['%s error: 0x%04X' % (name, self.data)]])
- self.data = self.count = 0
+ self.putd(show, want_len)
+ if check and not valid:
+ warn_show = bitpack(self.data)
+ self.putx([Ann.WARN, ['{} error: 0x{:04X}'.format(name, warn_show)]])
+ self.data = []
self.ss_bit = self.ss_start = self.samplenum
- return ret == 0
-
- def decode(self, ss, es, data):
- if self.samplerate is None:
- raise Exception("Cannot decode without samplerate.")
- for (self.samplenum, pins) in data:
- self.ir = pins[0]
-
- # Wait for an "interesting" edge, but also record the other ones.
- if self.old_ir == self.ir:
- continue
- if self.ir != self.active:
+ return valid
+
+ def decode(self):
+ if not self.samplerate:
+ raise SamplerateError('Cannot decode without samplerate.')
+ self.calc_rate()
+
+ cd_count = None
+ if self.options['cd_freq']:
+ cd_count = int(self.samplerate / self.options['cd_freq']) + 1
+ prev_ir = None
+
+ if self.options['polarity'] == 'auto':
+ # Take sample 0 as reference.
+ curr_level, = self.wait({'skip': 0})
+ active = 1 - curr_level
+ else:
+ active = 0 if self.options['polarity'] == 'active-low' else 1
+ self.is_extended = self.options['extended'] == 'yes'
+ want_addr_len = 16 if self.is_extended else 8
+
+ while True:
+ # Detect changes in the presence of an active input signal.
+ # The decoder can either be fed an already filtered RX signal
+ # or optionally can detect the presence of a carrier. Periods
+ # of inactivity (signal changes slower than the carrier freq,
+ # if specified) pass on the most recently sampled level. This
+ # approach works for filtered and unfiltered input alike, and
+ # only slightly extends the active phase of input signals with
+ # carriers included by one period of the carrier frequency.
+ # IR based communication protocols can cope with this slight
+ # inaccuracy just fine by design. Enabling carrier detection
+ # on already filtered signals will keep the length of their
+ # active period, but will shift their signal changes by one
+ # carrier period before they get passed to decoding logic.
+ if cd_count:
+ (cur_ir,) = self.wait([{Pin.IR: 'e'}, {'skip': cd_count}])
+ if self.matched[0]:
+ cur_ir = active
+ if cur_ir == prev_ir:
+ continue
+ prev_ir = cur_ir
+ self.ir = cur_ir
+ else:
+ (self.ir,) = self.wait({Pin.IR: 'e'})
+
+ if self.ir != active:
+ # Save the location of the non-active edge (recessive),
+ # then wait for the next edge. Immediately process the
+ # end of the STOP bit which completes an IR frame.
self.ss_other_edge = self.samplenum
- self.old_ir = self.ir
- continue
+ if self.state != 'STOP':
+ continue
- b = self.samplenum - self.ss_bit
+ # Reset internal state for long periods of idle level.
+ width = self.samplenum - self.ss_bit
+ if width >= self.idle_to and self.state != 'STOP':
+ self.reset()
# State machine.
if self.state == 'IDLE':
- if b in range(self.lc - self.margin, self.lc + self.margin):
+ if self.compare_with_tolerance(width, self.lc):
self.putpause('Long')
- self.putx([5, ['Leader code', 'Leader', 'LC', 'L']])
+ self.putx([Ann.LEADER_CODE, ['Leader code', 'Leader', 'LC', 'L']])
self.ss_remote = self.ss_start
- self.data = self.count = 0
+ self.data = []
self.state = 'ADDRESS'
- elif b in range(self.rc - self.margin, self.rc + self.margin):
+ elif self.compare_with_tolerance(width, self.rc):
self.putpause('Short')
self.putstop(self.samplenum)
self.samplenum += self.stop
- self.putx([10, ['Repeat code', 'Repeat', 'RC', 'R']])
- self.data = self.count = 0
+ self.putx([Ann.REPEAT_CODE, ['Repeat code', 'Repeat', 'RC', 'R']])
+ self.data = []
self.ss_bit = self.ss_start = self.samplenum
elif self.state == 'ADDRESS':
- self.handle_bit(b)
- if self.count == 8:
- self.state = 'ADDRESS#' if self.data_ok() else 'IDLE'
+ self.handle_bit(width)
+ if len(self.data) == want_addr_len:
+ self.data_ok(False, want_addr_len)
+ self.state = 'COMMAND' if self.is_extended else 'ADDRESS#'
elif self.state == 'ADDRESS#':
- self.handle_bit(b)
- if self.count == 16:
- self.state = 'COMMAND' if self.data_ok() else 'IDLE'
+ self.handle_bit(width)
+ if len(self.data) == 16:
+ self.data_ok(True, 8)
+ self.state = 'COMMAND'
elif self.state == 'COMMAND':
- self.handle_bit(b)
- if self.count == 8:
- self.state = 'COMMAND#' if self.data_ok() else 'IDLE'
+ self.handle_bit(width)
+ if len(self.data) == 8:
+ self.data_ok(False, 8)
+ self.state = 'COMMAND#'
elif self.state == 'COMMAND#':
- self.handle_bit(b)
- if self.count == 16:
- self.state = 'STOP' if self.data_ok() else 'IDLE'
+ self.handle_bit(width)
+ if len(self.data) == 16:
+ self.data_ok(True, 8)
+ self.state = 'STOP'
elif self.state == 'STOP':
self.putstop(self.ss_bit)
self.putremote()
self.ss_bit = self.ss_start = self.samplenum
self.state = 'IDLE'
- else:
- raise Exception('Invalid state: %s' % self.state)
-
- self.old_ir = self.ir
-