From acba48696ef9dd516d2cdf90f89e099deb7e1a73 Mon Sep 17 00:00:00 2001 From: Uwe Hermann Date: Sat, 14 Jan 2012 18:40:43 +0100 Subject: [PATCH] srd: SPI: Add support for different CS# polarity. --- decoders/spi.py | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/decoders/spi.py b/decoders/spi.py index 5b97cd4..cf37620 100644 --- a/decoders/spi.py +++ b/decoders/spi.py @@ -30,8 +30,8 @@ CPOL_0 = 0 # Clock is low when inactive CPOL_1 = 1 # Clock is high when inactive # Clock phase options -CPHA_0 = 0 # Data is valid on the rising clock edge -CPHA_1 = 1 # Data is valid on the falling clock edge +CPHA_0 = 0 # Data is valid on the leading clock edge +CPHA_1 = 1 # Data is valid on the trailing clock edge # Bit order options MSB_FIRST = 0 @@ -67,7 +67,7 @@ class Decoder(srd.Decoder): {'id': 'cs', 'name': 'CS#', 'desc': 'SPI CS (chip select) line'}, ] options = { - 'cs_active_low': ['CS# active low', ACTIVE_LOW], + 'cs_polarity': ['CS# polarity', ACTIVE_LOW], 'cpol': ['Clock polarity', CPOL_0], 'cpha': ['Clock phase', CPHA_0], 'bitorder': ['Bit order within the SPI data', MSB_FIRST], @@ -87,7 +87,7 @@ class Decoder(srd.Decoder): self.cs_was_deasserted_during_data_word = 0 # Set protocol decoder option defaults. - self.cs_active_low = Decoder.options['cs_active_low'][1] + self.cs_polarity = Decoder.options['cs_polarity'][1] self.cpol = Decoder.options['cpol'][1] self.cpha = Decoder.options['cpha'][1] self.bitorder = Decoder.options['bitorder'][1] @@ -129,7 +129,8 @@ class Decoder(srd.Decoder): # If this is the first bit, save its sample number. if self.bitcount == 0: self.start_sample = samplenum - if cs: + deasserted = cs if (self.cs_polarity == ACTIVE_LOW) else not c + if deasserted: self.cs_was_deasserted_during_data_word = 1 # Receive MOSI bit into our shift register. @@ -158,7 +159,8 @@ class Decoder(srd.Decoder): if self.cs_was_deasserted_during_data_word: self.put(self.start_sample, self.samplenum, self.out_ann, - [ANN_HEX, ['WARNING: CS# was deasserted!']]) + [ANN_HEX, ['WARNING: CS# was deasserted during this ' + 'SPI data byte!']]) # Reset decoder state. self.mosidata = 0 -- 2.30.2