X-Git-Url: https://sigrok.org/gitweb/?p=libsigrokdecode.git;a=blobdiff_plain;f=decoders%2Fspi%2Fpd.py;h=85bb1cb9e3195464fc55a983d3e87ecc78cf0baf;hp=864bca6795d55d0e3ca9ffcfbc2196c61e0e41f6;hb=f04db50ab7bbc59b7668396500b92ae2d3418f0e;hpb=2824e81140d3a8e37464f758cf67f50f2f7afca7 diff --git a/decoders/spi/pd.py b/decoders/spi/pd.py index 864bca6..85bb1cb 100644 --- a/decoders/spi/pd.py +++ b/decoders/spi/pd.py @@ -15,8 +15,7 @@ ## 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 @@ -71,14 +70,11 @@ spi_mode = { (1, 1): 3, # Mode 3 } -class SamplerateError(Exception): - pass - class ChannelError(Exception): pass class Decoder(srd.Decoder): - api_version = 2 + api_version = 3 id = 'spi' name = 'SPI' longname = 'Serial Peripheral Interface' @@ -125,8 +121,10 @@ class Decoder(srd.Decoder): ) def __init__(self): + self.reset() + + def reset(self): self.samplerate = None - self.oldclk = 1 self.bitcount = 0 self.misodata = self.mosidata = 0 self.misobits = [] @@ -137,21 +135,19 @@ class Decoder(srd.Decoder): self.samplenum = -1 self.ss_transfer = -1 self.cs_was_deasserted = False - self.oldcs = None - self.oldpins = None self.have_cs = self.have_miso = self.have_mosi = None - self.no_cs_notification = False - - def metadata(self, key, value): - if key == srd.SRD_CONF_SAMPLERATE: - self.samplerate = value def start(self): self.out_python = self.register(srd.OUTPUT_PYTHON) self.out_ann = self.register(srd.OUTPUT_ANN) - self.out_bin = self.register(srd.OUTPUT_BINARY) + 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 metadata(self, key, value): + if key == srd.SRD_CONF_SAMPLERATE: + self.samplerate = value def putw(self, data): self.put(self.ss_block, self.samplenum, self.out_ann, data) @@ -165,10 +161,12 @@ class Decoder(srd.Decoder): if self.have_miso: ss, es = self.misobits[-1][1], self.misobits[0][2] - self.put(ss, es, self.out_bin, [0, bytes([so])]) + 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] - self.put(ss, es, self.out_bin, [1, bytes([si])]) + 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]) @@ -211,17 +209,18 @@ class Decoder(srd.Decoder): not self.cs_asserted(cs) if self.have_cs else False ws = self.options['wordsize'] + bo = self.options['bitorder'] # Receive MISO bit into our shift register. if self.have_miso: - if self.options['bitorder'] == 'msb-first': + if bo == 'msb-first': self.misodata |= miso << (ws - 1 - self.bitcount) else: self.misodata |= miso << self.bitcount # Receive MOSI bit into our shift register. if self.have_mosi: - if self.options['bitorder'] == 'msb-first': + if bo == 'msb-first': self.mosidata |= mosi << (ws - 1 - self.bitcount) else: self.mosidata |= mosi << self.bitcount @@ -253,22 +252,23 @@ class Decoder(srd.Decoder): self.putdata() # Meta bitrate. - elapsed = 1 / float(self.samplerate) - elapsed *= (self.samplenum - self.ss_block + 1) - bitrate = int(1 / elapsed * self.options['wordsize']) - self.put(self.ss_block, self.samplenum, self.out_bitrate, bitrate) + if self.samplerate: + elapsed = 1 / float(self.samplerate) + elapsed *= (self.samplenum - self.ss_block + 1) + bitrate = int(1 / elapsed * ws) + 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!']]) self.reset_decoder_state() - def find_clk_edge(self, miso, mosi, clk, cs): - if self.have_cs and self.oldcs != cs: + def find_clk_edge(self, miso, mosi, clk, cs, first): + if self.have_cs and (first or self.matched[self.have_cs]): # Send all CS# pin value changes. + oldcs = None if first else 1 - cs self.put(self.samplenum, self.samplenum, self.out_python, - ['CS-CHANGE', self.oldcs, cs]) - self.oldcs = cs + ['CS-CHANGE', oldcs, cs]) if self.cs_asserted(cs): self.ss_transfer = self.samplenum @@ -286,11 +286,9 @@ class Decoder(srd.Decoder): return # Ignore sample if the clock pin hasn't changed. - if clk == self.oldclk: + if first or not self.matched[0]: return - self.oldclk = clk - # Sample data on rising/falling clock edge (depends on mode). mode = spi_mode[self.options['cpol'], self.options['cpha']] if mode == 0 and clk == 0: # Sample on rising clock edge @@ -305,27 +303,35 @@ class Decoder(srd.Decoder): # Found the correct clock edge, now get the SPI bit(s). self.handle_bit(miso, mosi, clk, cs) - def decode(self, ss, es, data): - 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: - - # Ignore identical samples early on (for performance reasons). - if self.oldpins == pins: - continue - self.oldpins, (clk, miso, mosi, cs) = pins, pins - self.have_miso = (miso in (0, 1)) - self.have_mosi = (mosi in (0, 1)) - self.have_cs = (cs in (0, 1)) - - # Either MISO or MOSI (but not both) can be omitted. - if not (self.have_miso or self.have_mosi): - raise ChannelError('Either MISO or MOSI (or both) pins required.') - - # 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) + def decode(self): + # The CLK input is mandatory. Other signals are (individually) + # optional. Yet either MISO or MOSI (or both) must be provided. + # Tell stacked decoders when we don't have a CS# signal. + if not self.has_channel(0): + raise ChannelError('Either MISO or MOSI (or both) pins required.') + self.have_miso = self.has_channel(1) + self.have_mosi = self.has_channel(2) + if not self.have_miso and not self.have_mosi: + raise ChannelError('Either MISO or MOSI (or both) pins required.') + self.have_cs = self.has_channel(3) + if not self.have_cs: + self.put(0, 0, self.out_python, ['CS-CHANGE', None, None]) + + # We want all CLK changes. We want all CS changes if CS is used. + # Map 'have_cs' from boolean to an integer index. This simplifies + # evaluation in other locations. + wait_cond = [{0: 'e'}] + if self.have_cs: + self.have_cs = len(wait_cond) + wait_cond.append({3: 'e'}) + + # "Pixel compatibility" with the v2 implementation. Grab and + # process the very first sample before checking for edges. The + # previous implementation did this by seeding old values with + # None, which led to an immediate "change" in comparison. + (clk, miso, mosi, cs) = self.wait({}) + self.find_clk_edge(miso, mosi, clk, cs, True) + + while True: + (clk, miso, mosi, cs) = self.wait(wait_cond) + self.find_clk_edge(miso, mosi, clk, cs, False)