X-Git-Url: https://sigrok.org/gitweb/?p=libsigrokdecode.git;a=blobdiff_plain;f=decoders%2Fspi.py;h=457abb5bde2f962cdd2c325023944eb6e9017aa9;hp=eaf60ef38bdb27fd1f52b9edd87bdde2a44e9e26;hb=0db89774dee57db500f270985f73f3bb2dcdbb42;hpb=4917bb31c6a1e3e77418ac446650a6d9aa3e528b diff --git a/decoders/spi.py b/decoders/spi.py index eaf60ef..457abb5 100644 --- a/decoders/spi.py +++ b/decoders/spi.py @@ -2,6 +2,7 @@ ## This file is part of the sigrok project. ## ## Copyright (C) 2011 Gareth McMullin +## Copyright (C) 2012 Uwe Hermann ## ## This program is free software; you can redistribute it and/or modify ## it under the terms of the GNU General Public License as published by @@ -20,6 +21,25 @@ import sigrokdecode as srd +# Chip-select options +ACTIVE_LOW = 0 +ACTIVE_HIGH = 1 + +# Clock polarity options +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 + +# Bit order options +MSB_FIRST = 0 +LSB_FIRST = 1 + +# Annotation formats +ANN_HEX = 0 + class Decoder(srd.Decoder): id = 'spi' name = 'SPI' @@ -32,22 +52,41 @@ class Decoder(srd.Decoder): inputs = ['logic'] outputs = ['spi'] probes = [ - {'id': 'sdata', 'name': 'DATA', 'desc': 'SPI data line (MISO or MOSI)'}, + {'id': 'mosi', 'name': 'MOSI', + 'desc': 'SPI MOSI line (Master out, slave in)'}, + {'id': 'miso', 'name': 'MISO', + 'desc': 'SPI MISO line (Master in, slave out)'}, {'id': 'sck', 'name': 'CLK', 'desc': 'SPI clock line'}, + {'id': 'cs', 'name': 'CS#', 'desc': 'SPI CS (chip select) line'}, ] - options = {} + options = { + 'cs_active_low': ['CS# active low', ACTIVE_LOW], + 'clock_polarity': ['Clock polarity', CPOL_0], + 'clock_phase': ['Clock phase', CPHA_0], + 'bit_order': ['Bit order within the SPI data', MSB_FIRST], + 'word_size': ['Word size of SPI data', 8], # 1-64? + } annotations = [ - ['TODO', 'TODO'], + ['Hex', 'SPI data bytes in hex format'], ] def __init__(self): self.oldsck = 1 self.bitcount = 0 self.mosidata = 0 + self.misodata = 0 self.bytesreceived = 0 + self.samplenum = -1 + + # Set protocol decoder option defaults. + self.cs_active_low = Decoder.options['cs_active_low'][1] + self.clock_polarity = Decoder.options['clock_polarity'][1] + self.clock_phase = Decoder.options['clock_phase'][1] + self.bit_order = Decoder.options['bit_order'][1] + self.word_size = Decoder.options['word_size'][1] def start(self, metadata): - # self.out_proto = self.add(srd.OUTPUT_PROTO, 'spi') + self.out_proto = self.add(srd.OUTPUT_PROTO, 'spi') self.out_ann = self.add(srd.OUTPUT_ANN, 'spi') def report(self): @@ -56,24 +95,28 @@ class Decoder(srd.Decoder): def decode(self, ss, es, data): # HACK! At the moment the number of probes is not handled correctly. # E.g. if an input file (-i foo.sr) has more than two probes enabled. - # for (samplenum, (sdata, sck, x, y, z, a)) in data: + # for (samplenum, (mosi, sck, x, y, z, a)) in data: # for (samplenum, (cs, miso, sck, mosi, wp, hold)) in data: - for (samplenum, (cs, miso, sck, sdata, wp, hold)) in data: + for (samplenum, (cs, miso, sck, mosi, wp, hold)) in data: + + self.samplenum += 1 # FIXME - # Sample SDATA on rising SCK. + # Sample data on rising SCK edges. if sck == self.oldsck: continue self.oldsck = sck if sck == 0: continue - # If this is the first bit, save timestamp. + # If this is the first bit, save its sample number. if self.bitcount == 0: - self.time = samplenum + self.start_sample = samplenum # Receive bit into our shift register. - if sdata == 1: + if mosi == 1: self.mosidata |= 1 << (7 - self.bitcount) + if miso == 1: + self.misodata |= 1 << (7 - self.bitcount) self.bitcount += 1 @@ -81,11 +124,15 @@ class Decoder(srd.Decoder): if self.bitcount != 8: continue - # self.put(0, 0, self.out_proto, out_proto) # TODO - self.put(0, 0, self.out_ann, [0, ['0x%02x' % self.mosidata]]) + self.put(self.start_sample, self.samplenum, self.out_proto, + ['data', self.mosidata, self.misodata]) + self.put(self.start_sample, self.samplenum, self.out_ann, + [ANN_HEX, ['MOSI: 0x%02x, MISO: 0x%02x' % (self.mosidata, + self.misodata)]]) # Reset decoder state. self.mosidata = 0 + self.misodata = 0 self.bitcount = 0 # Keep stats for summary.