diff options
Diffstat (limited to 'decoders/spi/pd.py')
| -rw-r--r-- | decoders/spi/pd.py | 23 |
1 files changed, 13 insertions, 10 deletions
diff --git a/decoders/spi/pd.py b/decoders/spi/pd.py index bb486c8..b6c96bc 100644 --- a/decoders/spi/pd.py +++ b/decoders/spi/pd.py @@ -48,9 +48,10 @@ class Decoder(srd.Decoder): {'id': 'mosi', 'name': 'MOSI', 'desc': 'SPI MOSI line (Master out, slave in)'}, {'id': 'sck', 'name': 'CLK', 'desc': 'SPI clock line'}, - {'id': 'cs', 'name': 'CS#', 'desc': 'SPI CS (chip select) line'}, ] - optional_probes = [] # TODO + optional_probes = [ + {'id': 'cs', 'name': 'CS#', 'desc': 'SPI chip-select line'}, + ] options = { 'cs_polarity': ['CS# polarity', 'active-low'], 'cpol': ['Clock polarity', 0], @@ -96,10 +97,11 @@ class Decoder(srd.Decoder): # If this is the first bit, save its sample number. if self.bitcount == 0: self.startsample = self.samplenum - active_low = (self.options['cs_polarity'] == 'active-low') - deasserted = cs if active_low else not cs - if deasserted: - self.cs_was_deasserted_during_data_word = 1 + if self.have_cs: + active_low = (self.options['cs_polarity'] == 'active-low') + deasserted = cs if active_low else not cs + if deasserted: + self.cs_was_deasserted_during_data_word = 1 ws = self.options['wordsize'] @@ -130,19 +132,19 @@ class Decoder(srd.Decoder): self.putw([3, ['CS# was deasserted during this data word!']]) # Reset decoder state. - self.mosidata = 0 - self.misodata = 0 - self.bitcount = 0 + self.mosidata = self.misodata = self.bitcount = 0 # Keep stats for summary. self.bytesreceived += 1 def find_clk_edge(self, miso, mosi, sck, cs): - if self.oldcs != cs: + if self.have_cs and self.oldcs != cs: # Send all CS# pin value changes. self.put(self.samplenum, self.samplenum, self.out_proto, ['CS-CHANGE', self.oldcs, cs]) self.oldcs = cs + # Reset decoder state when CS# changes (and the CS# pin is used). + self.mosidata = self.misodata = self.bitcount= 0 # Ignore sample if the clock pin hasn't changed. if sck == self.oldsck: @@ -172,6 +174,7 @@ class Decoder(srd.Decoder): if self.oldpins == pins: continue self.oldpins, (miso, mosi, sck, cs) = pins, pins + self.have_cs = (cs in (0, 1)) # State machine. if self.state == 'IDLE': |