diff options
Diffstat (limited to 'decoders')
| -rw-r--r-- | decoders/numbers_and_state/__init__.py | 41 | ||||
| -rw-r--r-- | decoders/numbers_and_state/pd.py | 377 |
2 files changed, 418 insertions, 0 deletions
diff --git a/decoders/numbers_and_state/__init__.py b/decoders/numbers_and_state/__init__.py new file mode 100644 index 0000000..4fe42a3 --- /dev/null +++ b/decoders/numbers_and_state/__init__.py @@ -0,0 +1,41 @@ +## +## This file is part of the libsigrokdecode project. +## +## Copyright (C) 2019 Comlab AG +## Copyright (C) 2020 Gerhard Sittig <gerhard.sittig@gmx.net> +## +## 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 +## the Free Software Foundation; either version 2 of the License, or +## (at your option) any later version. +## +## This program is distributed in the hope that it will be useful, +## but WITHOUT ANY WARRANTY; without even the implied warranty of +## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +## 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, see <http://www.gnu.org/licenses/>. +## + +''' +This protocol decoder takes a set of logic input signals, and interprets +their bit pattern according to user specifications as different kinds of +numbers, or an enumeration of e.g. machine states. + +Supported formats are: signed and unsigned integers, fixed point numbers, +IEEE754 floating point numbers, and number to text mapping controlled by +external data files. (Support for half precision floats depends on the +Python runtime, and may not universally be available.) + +User provided text mapping files can either use the JSON format: + {"one": 1, "two": 2, "four": 4} +or the Python programming language: + enumtext = { 1: "one", 2: "two", 3: "three", } + +In addition to all enum values on one row (sequential presentation of +the data), a limited number of enum values also are shown in tabular +presentation, which can help visualize state machines or task switches. +''' + +from .pd import Decoder diff --git a/decoders/numbers_and_state/pd.py b/decoders/numbers_and_state/pd.py new file mode 100644 index 0000000..b8ac87e --- /dev/null +++ b/decoders/numbers_and_state/pd.py @@ -0,0 +1,377 @@ +## +## This file is part of the libsigrokdecode project. +## +## Copyright (C) 2019 Comlab AG +## Copyright (C) 2020 Gerhard Sittig <gerhard.sittig@gmx.net> +## +## 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 +## the Free Software Foundation; either version 2 of the License, or +## (at your option) any later version. +## +## This program is distributed in the hope that it will be useful, +## but WITHOUT ANY WARRANTY; without even the implied warranty of +## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +## 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, see <http://www.gnu.org/licenses/>. +## + +# This implementation started as a "vector slicer", then turned into the +# "numbers and states" decoder, because users always had the freedom to +# connect any logic signal to either of the decoder inputs. That's when +# slicing vectors took second seat, and just was not needed any longer +# in the strict sense. +# +# TODO +# - Find an appropriate number of input channels, and maximum enum slots. +# - Re-check correctness of signed integers. Signed fixed point is based +# on integers and transparently benefits from fixes and improvements. +# - Local formatting in individual decoders becomes obsolete when common +# support for user selected formatting gets introduced. +# - There is overlap with the 'parallel' decoder. Ideally the numbers +# decoder could stack on top of parallel, but parallel currently is +# severely limited in its number of input channels, and dramatically +# widening the parallel decoder may be undesirable. + +from common.srdhelper import bitpack +import json +import sigrokdecode as srd +import struct + +''' +OUTPUT_PYTHON format: + +Packet: +[<ptype>, <pdata>] + +This is a list of <ptype>s and their respective <pdata> values: + - 'RAW': The data is a tuple of bit count and bit pattern (a number, + assuming unsigned integer presentation of the input data bit pattern). + - 'NUMBER': The data is the conversion result of the bit pattern. + - 'ENUM': The data is a tuple of the raw number and its mapped text. +''' + +# TODO Better raise the number of channels to 32. This allows access to +# IEEE754 single precision numbers, and shall cover most busses, _and_ +# remains within most logic analyzers' capabilities, and keeps the UI +# dialog somewhat managable. What's a good default for the number of +# enum slots (which translate to annotation rows)? Notice that 2 to the +# power of the channel count is way out of the question. :) +_max_channels = 16 +_max_enum_slots = 32 + +class ChannelError(Exception): + pass + +class Pin: + CLK, BIT_0 = range(2) + BIT_N = BIT_0 + _max_channels + +class Ann: + RAW, NUM = range(2) + ENUM_0 = NUM + 1 + ENUM_OVR = ENUM_0 + _max_enum_slots + ENUMS = range(ENUM_0, ENUM_OVR) + WARN = ENUM_OVR + 1 + + @staticmethod + def enum_indices(): + return [i for i in range(Ann.ENUMS)] + + @staticmethod + def get_enum_idx(code): + if code in range(_max_enum_slots): + return Ann.ENUM_0 + code + return Ann.ENUM_OVR + +def _channel_decl(count): + return tuple([ + {'id': 'bit{}'.format(i), 'name': 'Bit{}'.format(i), 'desc': 'Bit position {}'.format(i)} + for i in range(count) + ]) + +def _enum_cls_decl(count): + return tuple([ + ('enum{}'.format(i), 'Enumeration slot {}'.format(i)) + for i in range(count) + ] + [('enumovr', 'Enumeration overflow')]) + +def _enum_rows_decl(count): + return tuple([ + ('enums{}'.format(i), 'Enumeration slots {}'.format(i), (Ann.ENUM_0 + i,)) + for i in range(count) + ] + [('enumsovr', 'Enumeration overflows', (Ann.ENUM_OVR,))]) + +class Decoder(srd.Decoder): + api_version = 3 + id = 'numbers_and_state' + name = 'Numbers and State' + longname = 'Interpret bit patters as numbers or state enums' + desc = 'Interpret bit patterns as different kinds of numbers (integer, float, enum).' + license = 'gplv2+' + inputs = ['logic'] + outputs = ['numbers_and_state'] + tags = ['Encoding', 'Util'] + optional_channels = ( + {'id': 'clk', 'name': 'Clock', 'desc': 'Clock'}, + ) + _channel_decl(_max_channels) + options = ( + {'id': 'clkedge', 'desc': 'Clock edge', 'default': 'rising', + 'values': ('rising', 'falling', 'either')}, + {'id': 'count', 'desc': 'Total bits count', 'default': 0}, + {'id': 'interp', 'desc': 'Interpretation', 'default': 'unsigned', + 'values': ('unsigned', 'signed', 'fixpoint', 'fixsigned', 'ieee754', 'enum')}, + {'id': 'fracbits', 'desc': 'Fraction bits count', 'default': 0}, + {'id': 'mapping', 'desc': 'Enum to text map file', + 'default': 'enumtext.json'}, + {'id': 'format', 'desc': 'Number format', 'default': '-', + 'values': ('-', 'bin', 'oct', 'dec', 'hex')}, + ) + annotations = ( + ('raw', 'Raw pattern'), + ('number', 'Number'), + ) + _enum_cls_decl(_max_enum_slots) + ( + ('warning', 'Warning'), + ) + annotation_rows = ( + ('raws', 'Raw bits', (Ann.RAW,)), + ('numbers', 'Numbers', (Ann.NUM,)), + ) + _enum_rows_decl(_max_enum_slots) + ( + ('warnings', 'Warnings', (Ann.WARN,)), + ) + + def __init__(self): + self.reset() + + def reset(self): + pass + + def start(self): + self.out_ann = self.register(srd.OUTPUT_ANN) + self.out_python = self.register(srd.OUTPUT_PYTHON) + + def putg(self, ss, es, cls, data): + self.put(ss, es, self.out_ann, [cls, data]) + + def putpy(self, ss, es, ptype, pdata): + self.put(ss, es, self.out_python, (ptype, pdata)) + + def grab_pattern(self, pins): + '''Get a bit pattern from potentially incomplete probes' values.''' + + # Pad and trim the input data, to achieve the user specified + # total number of bits. Map all unassigned signals to 0 (low). + # Return raw number (unsigned integer interpreation). + bits = pins + (None,) * self.bitcount + bits = bits[:self.bitcount] + bits = [b if b in (0, 1) else 0 for b in bits] + pattern = bitpack(bits) + return pattern + + def handle_pattern(self, ss, es, pattern): + fmt = '{{:0{}b}}'.format(self.bitcount) + txt = fmt.format(pattern) + self.putg(ss, es, Ann.RAW, [txt]) + self.putpy(ss, es, 'RAW', (self.bitcount, pattern)) + + try: + value = self.interpreter(ss, es, pattern) + except: + value = None + if value is None: + return + self.putpy(ss, es, 'NUMBER', value) + try: + formatted = self.formatter(ss, es, value) + except: + formatted = None + if formatted: + self.putg(ss, es, Ann.NUM, formatted) + if self.interpreter == self.interp_enum: + cls = Ann.get_enum_idx(pattern) + self.putg(ss, es, cls, formatted) + self.putpy(ss, es, 'ENUM', (value, formatted)) + + def interp_unsigned(self, ss, es, pattern): + value = pattern + return value + + def interp_signed(self, ss, es, pattern): + if not 'signmask' in self.interp_state: + self.interp_state.update({ + 'signmask': 1 << (self.bitcount - 1), + 'signfull': 1 << self.bitcount, + }) + is_neg = pattern & self.interp_state['signmask'] + if is_neg: + value = -(self.interp_state['signfull'] - pattern) + else: + value = pattern + return value + + def interp_fixpoint(self, ss, es, pattern): + if not 'fixdiv' in self.interp_state: + self.interp_state.update({ + 'fixsign': self.options['interp'] == 'fixsigned', + 'fixdiv': 2 ** self.options['fracbits'], + }) + if self.interp_state['fixsign']: + value = self.interp_signed(ss, es, pattern) + else: + value = self.interp_unsigned(ss, es, pattern) + value /= self.interp_state['fixdiv'] + return value + + def interp_ieee754(self, ss, es, pattern): + if not 'ieee_has_16bit' in self.interp_state: + self.interp_state.update({ + 'ieee_fmt_int_16': '=H', + 'ieee_fmt_flt_16': '=e', + 'ieee_fmt_int_32': '=L', + 'ieee_fmt_flt_32': '=f', + 'ieee_fmt_int_64': '=Q', + 'ieee_fmt_flt_64': '=d', + }) + try: + fmt = self.interp_state.update['ieee_fmt_flt_16'] + has_16bit_support = 8 * struct.calcsize(fmt) == 16 + except: + has_16bit_support = False + self.interp_state['ieee_has_16bit'] = has_16bit_support + if self.bitcount == 16: + if not self.interp_state['ieee_has_16bit']: + return None + buff = struct.pack(self.interp_state['ieee_fmt_int_16'], pattern) + value, = struct.unpack(self.interp_state['ieee_fmt_flt_16'], buff) + return value + if self.bitcount == 32: + buff = struct.pack(self.interp_state['ieee_fmt_int_32'], pattern) + value, = struct.unpack(self.interp_state['ieee_fmt_flt_32'], buff) + return value + if self.bitcount == 64: + buff = struct.pack(self.interp_state['ieee_fmt_int_64'], pattern) + value, = struct.unpack(self.interp_state['ieee_fmt_flt_64'], buff) + return value + return None + + def interp_enum(self, ss, es, pattern): + if not 'enum_map' in self.interp_state: + self.interp_state.update({ + 'enum_fn': self.options['mapping'], + 'enum_map': {}, + 'enum_have_map': False, + }) + try: + fn = self.interp_state['enum_fn'] + # TODO Optionally try in several locations? Next to the + # decoder implementation? Where else? Expect users to + # enter absolute paths? + with open(fn, 'r') as f: + maptext = f.read() + maptable = {} + if fn.endswith('.js') or fn.endswith('.json'): + # JSON requires string literals on the LHS, so the + # table is written "in reverse order". + js_table = json.loads(maptext) + for k, v in js_table.items(): + maptable[v] = k + elif fn.endswith('.py'): + # Expect a specific identifier at the Python module + # level, and assume that it's a dictionary. + py_table = {} + exec(maptext, py_table) + maptable.update(py_table['enumtext']) + self.interp_state['enum_map'].update(maptable) + self.interp_state['enum_have_map'] = True + except: + # Silently ignore failure. This happens while the user + # is typing the filename, and is non-fatal. If the file + # exists and is not readable or not valid or of unknown + # format, the worst thing that can happen is that the + # decoder implementation keeps using "anonymous" phrases + # until a mapping has become available. No harm is done. + # This decoder cannot tell intermediate from final file + # read attempts, so we cannot raise severity here. + pass + value = self.interp_state['enum_map'].get(pattern, None) + if value is None: + value = pattern + return value + + def format_native(self, ss, es, value): + return ['{}'.format(value),] + + def format_bin(self, ss, es, value): + if not self.format_string: + self.format_string = '{{:0{}b}}'.format(self.bitcount) + return [self.format_string.format(value)] + + def format_oct(self, ss, es, value): + if not self.format_string: + self.format_string = '{{:0{}o}}'.format((self.bitcount + 3 - 1) // 3) + return [self.format_string.format(value)] + + def format_dec(self, ss, es, value): + if not self.format_string: + self.format_string = '{:d}' + return [self.format_string.format(value)] + + def format_hex(self, ss, es, value): + if not self.format_string: + self.format_string = '{{:0{}x}}'.format((self.bitcount + 4 - 1) // 4) + return [self.format_string.format(value)] + + def decode(self): + channels = [ch for ch in range(_max_channels) if self.has_channel(ch)] + have_clk = Pin.CLK in channels + if have_clk: + channels.remove(Pin.CLK) + if not channels: + raise ChannelError("Need at least one bit channel.") + if have_clk: + clkedge = { + 'rising': 'r', + 'falling': 'f', + 'either': 'e', + }.get(self.options['clkedge']) + wait_cond = {Pin.CLK: clkedge} + else: + wait_cond = [{ch: 'e'} for ch in channels] + + bitcount = self.options['count'] + if not bitcount: + bitcount = channels[-1] - Pin.BIT_0 + 1 + self.bitcount = bitcount + + self.interpreter = { + 'unsigned': self.interp_unsigned, + 'signed': self.interp_signed, + 'fixpoint': self.interp_fixpoint, + 'fixsigned': self.interp_fixpoint, + 'ieee754': self.interp_ieee754, + 'enum': self.interp_enum, + }.get(self.options['interp']) + self.interp_state = {} + self.formatter = { + '-': self.format_native, + 'bin': self.format_bin, + 'oct': self.format_oct, + 'dec': self.format_dec, + 'hex': self.format_hex, + }.get(self.options['format']) + self.format_string = None + + pins = self.wait() + ss = self.samplenum + prev_pattern = self.grab_pattern(pins[Pin.BIT_0:]) + while True: + pins = self.wait(wait_cond) + es = self.samplenum + pattern = self.grab_pattern(pins[Pin.BIT_0:]) + if pattern == prev_pattern: + continue + self.handle_pattern(ss, es, prev_pattern) + ss = es + prev_pattern = pattern |