X-Git-Url: https://sigrok.org/gitweb/?p=libsigrokdecode.git;a=blobdiff_plain;f=decoders%2Fspi%2Fpd.py;h=4c5aa05e6a7782b0cf934f203dafb6d9b5637292;hp=6a2b5faff082c7e2d1369d44009d321ac14ec82d;hb=4539e9ca58966ce3c9cad4801b16c315e86ace01;hpb=84c1c0b52820af2418186ac3ecf93a5c6373a22e diff --git a/decoders/spi/pd.py b/decoders/spi/pd.py index 6a2b5fa..4c5aa05 100644 --- a/decoders/spi/pd.py +++ b/decoders/spi/pd.py @@ -15,29 +15,37 @@ ## 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 . ## import sigrokdecode as srd +from collections import namedtuple + +Data = namedtuple('Data', ['ss', 'es', 'val']) ''' OUTPUT_PYTHON format: -SPI packet: -[, , ] +Packet: +[, , ] -Commands: - - 'DATA': contains the MISO data, contains the MOSI data. +: + - 'DATA': contains the MOSI data, contains the MISO data. The data is _usually_ 8 bits (but can also be fewer or more bits). Both data items are Python numbers (not strings), or None if the respective - probe was not supplied. - - 'BITS': / contain a list of bit values in this MISO/MOSI data + channel was not supplied. + - 'BITS': / contain a list of bit values in this MOSI/MISO data item, and for each of those also their respective start-/endsample numbers. - - 'CS CHANGE': is the old CS# pin value, is the new value. - Both data items are Python numbers (0/1), not strings. + - 'CS-CHANGE': is the old CS# pin value, is the new value. + Both data items are Python numbers (0/1), not strings. At the beginning of + the decoding a packet is generated with = None and being the + initial state of the CS# pin or None if the chip select pin is not supplied. + - 'TRANSFER': / contain a list of Data() namedtuples for each + byte transferred during this block of CS# asserted time. Each Data() has + fields ss, es, and val. Examples: + ['CS-CHANGE', None, 1] ['CS-CHANGE', 1, 0] ['DATA', 0xff, 0x3a] ['BITS', [[1, 80, 82], [1, 83, 84], [1, 85, 86], [1, 87, 88], @@ -48,6 +56,8 @@ Examples: ['DATA', 0xa8, None] ['DATA', None, 0x55] ['CS-CHANGE', 0, 1] + ['TRANSFER', [Data(ss=80, es=96, val=0xff), ...], + [Data(ss=80, es=96, val=0x3a), ...]] ''' # Key: (CPOL, CPHA). Value: SPI mode. @@ -60,8 +70,14 @@ spi_mode = { (1, 1): 3, # Mode 3 } +class SamplerateError(Exception): + pass + +class ChannelError(Exception): + pass + class Decoder(srd.Decoder): - api_version = 1 + api_version = 2 id = 'spi' name = 'SPI' longname = 'Serial Peripheral Interface' @@ -69,14 +85,14 @@ class Decoder(srd.Decoder): license = 'gplv2+' inputs = ['logic'] outputs = ['spi'] - probes = [ + channels = ( {'id': 'clk', 'name': 'CLK', 'desc': 'Clock'}, - ] - optional_probes = [ + ) + optional_channels = ( {'id': 'miso', 'name': 'MISO', 'desc': 'Master in, slave out'}, {'id': 'mosi', 'name': 'MOSI', 'desc': 'Master out, slave in'}, {'id': 'cs', 'name': 'CS#', 'desc': 'Chip-select'}, - ] + ) options = ( {'id': 'cs_polarity', 'desc': 'CS# polarity', 'default': 'active-low', 'values': ('active-low', 'active-high')}, @@ -84,17 +100,17 @@ class Decoder(srd.Decoder): 'values': (0, 1)}, {'id': 'cpha', 'desc': 'Clock phase', 'default': 0, 'values': (0, 1)}, - {'id': 'bitorder', 'desc': 'Bit order within the SPI data', + {'id': 'bitorder', 'desc': 'Bit order', 'default': 'msb-first', 'values': ('msb-first', 'lsb-first')}, - {'id': 'wordsize', 'desc': 'Word size of SPI data', 'default': 8}, + {'id': 'wordsize', 'desc': 'Word size', 'default': 8}, + ) + annotations = ( + ('miso-data', 'MISO data'), + ('mosi-data', 'MOSI data'), + ('miso-bits', 'MISO bits'), + ('mosi-bits', 'MOSI bits'), + ('warnings', 'Human-readable warnings'), ) - annotations = [ - ['miso-data', 'MISO data'], - ['mosi-data', 'MOSI data'], - ['miso-bits', 'MISO bits'], - ['mosi-bits', 'MOSI bits'], - ['warnings', 'Human-readable warnings'], - ] annotation_rows = ( ('miso-data', 'MISO data', (0,)), ('miso-bits', 'MISO bits', (2,)), @@ -102,6 +118,10 @@ class Decoder(srd.Decoder): ('mosi-bits', 'MOSI bits', (3,)), ('other', 'Other', (4,)), ) + binary = ( + ('miso', 'MISO'), + ('mosi', 'MOSI'), + ) def __init__(self): self.samplerate = None @@ -110,13 +130,16 @@ class Decoder(srd.Decoder): self.misodata = self.mosidata = 0 self.misobits = [] self.mosibits = [] - self.startsample = -1 + self.misobytes = [] + self.mosibytes = [] + self.ss_block = -1 self.samplenum = -1 + self.ss_transfer = -1 self.cs_was_deasserted = False - self.oldcs = -1 + self.oldcs = None self.oldpins = None self.have_cs = self.have_miso = self.have_mosi = None - self.state = 'IDLE' + self.no_cs_notification = False def metadata(self, key, value): if key == srd.SRD_CONF_SAMPLERATE: @@ -125,11 +148,13 @@ class Decoder(srd.Decoder): def start(self): self.out_python = self.register(srd.OUTPUT_PYTHON) self.out_ann = self.register(srd.OUTPUT_ANN) + self.out_binary = self.register(srd.OUTPUT_BINARY) self.out_bitrate = self.register(srd.OUTPUT_META, meta=(int, 'Bitrate', 'Bitrate during transfers')) + self.bw = (self.options['wordsize'] + 7) // 8 def putw(self, data): - self.put(self.startsample, self.samplenum, self.out_ann, data) + self.put(self.ss_block, self.samplenum, self.out_ann, data) def putdata(self): # Pass MISO and MOSI bits and then data to the next PD up the stack. @@ -140,12 +165,21 @@ class Decoder(srd.Decoder): if self.have_miso: ss, es = self.misobits[-1][1], self.misobits[0][2] + bdata = so.to_bytes(self.bw, byteorder='big') + self.put(ss, es, self.out_binary, [0, bdata]) if self.have_mosi: ss, es = self.mosibits[-1][1], self.mosibits[0][2] + bdata = si.to_bytes(self.bw, byteorder='big') + self.put(ss, es, self.out_binary, [1, bdata]) self.put(ss, es, self.out_python, ['BITS', si_bits, so_bits]) self.put(ss, es, self.out_python, ['DATA', si, so]) + if self.have_miso: + self.misobytes.append(Data(ss=ss, es=es, val=so)) + if self.have_mosi: + self.mosibytes.append(Data(ss=ss, es=es, val=si)) + # Bit annotations. if self.have_miso: for bit in self.misobits: @@ -167,16 +201,16 @@ class Decoder(srd.Decoder): self.mosibits = [] if self.have_mosi else None self.bitcount = 0 + def cs_asserted(self, cs): + active_low = (self.options['cs_polarity'] == 'active-low') + return (cs == 0) if active_low else (cs == 1) + def handle_bit(self, miso, mosi, clk, cs): # If this is the first bit of a dataword, save its sample number. if self.bitcount == 0: - self.startsample = self.samplenum - self.cs_was_deasserted = False - if self.have_cs: - active_low = (self.options['cs_polarity'] == 'active-low') - deasserted = (cs == 1) if active_low else (cs == 0) - if deasserted: - self.cs_was_deasserted = True + self.ss_block = self.samplenum + self.cs_was_deasserted = \ + not self.cs_asserted(cs) if self.have_cs else False ws = self.options['wordsize'] @@ -222,9 +256,9 @@ class Decoder(srd.Decoder): # Meta bitrate. elapsed = 1 / float(self.samplerate) - elapsed *= (self.samplenum - self.startsample + 1) + elapsed *= (self.samplenum - self.ss_block + 1) bitrate = int(1 / elapsed * self.options['wordsize']) - self.put(self.startsample, self.samplenum, self.out_bitrate, bitrate) + self.put(self.ss_block, self.samplenum, self.out_bitrate, bitrate) if self.have_cs and self.cs_was_deasserted: self.putw([4, ['CS# was deasserted during this data word!']]) @@ -237,9 +271,22 @@ class Decoder(srd.Decoder): self.put(self.samplenum, self.samplenum, self.out_python, ['CS-CHANGE', self.oldcs, cs]) self.oldcs = cs + + if self.cs_asserted(cs): + self.ss_transfer = self.samplenum + self.misobytes = [] + self.mosibytes = [] + else: + self.put(self.ss_transfer, self.samplenum, self.out_python, + ['TRANSFER', self.mosibytes, self.misobytes]) + # Reset decoder state when CS# changes (and the CS# pin is used). self.reset_decoder_state() + # We only care about samples if CS# is asserted. + if self.have_cs and not self.cs_asserted(cs): + return + # Ignore sample if the clock pin hasn't changed. if clk == self.oldclk: return @@ -261,8 +308,8 @@ class Decoder(srd.Decoder): self.handle_bit(miso, mosi, clk, cs) def decode(self, ss, es, data): - if self.samplerate is None: - raise Exception("Cannot decode without samplerate.") + if not self.samplerate: + raise SamplerateError('Cannot decode without samplerate.') # Either MISO or MOSI can be omitted (but not both). CS# is optional. for (self.samplenum, pins) in data: @@ -276,11 +323,11 @@ class Decoder(srd.Decoder): # Either MISO or MOSI (but not both) can be omitted. if not (self.have_miso or self.have_mosi): - raise Exception('Either MISO or MOSI (or both) pins required.') + raise ChannelError('Either MISO or MOSI (or both) pins required.') - # State machine. - if self.state == 'IDLE': - self.find_clk_edge(miso, mosi, clk, cs) - else: - raise Exception('Invalid state: %s' % self.state) + # Tell stacked decoders that we don't have a CS# signal. + if not self.no_cs_notification and not self.have_cs: + self.put(0, 0, self.out_python, ['CS-CHANGE', None, None]) + self.no_cs_notification = True + self.find_clk_edge(miso, mosi, clk, cs)