mirror of
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506 lines
21 KiB
Python
Executable File
506 lines
21 KiB
Python
Executable File
##
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## This file is part of the libsigrokdecode project.
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##
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## Copyright (C) 2017 Gerhard Sittig <gerhard.sittig@gmx.net>
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## Copyright (C) 2019 DreamSourceLab <support@dreamsourcelab.com>
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##
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## This program is free software; you can redistribute it and/or modify
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## it under the terms of the GNU General Public License as published by
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## the Free Software Foundation; either version 2 of the License, or
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## (at your option) any later version.
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##
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## This program is distributed in the hope that it will be useful,
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## but WITHOUT ANY WARRANTY; without even the implied warranty of
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## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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## GNU General Public License for more details.
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##
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## You should have received a copy of the GNU General Public License
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## along with this program; if not, see <http://www.gnu.org/licenses/>.
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##
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# This implementation is incomplete. TODO items:
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# - Support the optional RESET# pin, detect cold and warm reset.
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# - Split slot values into audio samples of their respective width and
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# frequency (either on user provided parameters, or from inspection of
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# decoded register access).
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import sigrokdecode as srd
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class ChannelError(Exception):
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pass
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class Pins:
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(SYNC, BIT_CLK, SDATA_OUT, SDATA_IN, RESET) = range(5)
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class Ann:
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(
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BITS_OUT, BITS_IN,
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SLOT_OUT_RAW, SLOT_OUT_TAG, SLOT_OUT_ADDR, SLOT_OUT_DATA,
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SLOT_OUT_03, SLOT_OUT_04, SLOT_OUT_05, SLOT_OUT_06,
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SLOT_OUT_07, SLOT_OUT_08, SLOT_OUT_09, SLOT_OUT_10,
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SLOT_OUT_11, SLOT_OUT_IO,
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SLOT_IN_RAW, SLOT_IN_TAG, SLOT_IN_ADDR, SLOT_IN_DATA,
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SLOT_IN_03, SLOT_IN_04, SLOT_IN_05, SLOT_IN_06,
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SLOT_IN_07, SLOT_IN_08, SLOT_IN_09, SLOT_IN_10,
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SLOT_IN_11, SLOT_IN_IO,
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WARN, ERROR,
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) = range(32)
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(
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BIN_FRAME_OUT,
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BIN_FRAME_IN,
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BIN_SLOT_RAW_OUT,
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BIN_SLOT_RAW_IN,
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) = range(4)
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class Decoder(srd.Decoder):
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api_version = 3
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id = 'ac97'
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name = "AC '97"
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longname = "Audio Codec '97"
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desc = 'Audio and modem control for PC systems.'
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license = 'gplv2+'
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inputs = ['logic']
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outputs = []
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tags = ['Audio', 'PC']
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channels = (
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{'id': 'sync', 'name': 'SYNC', 'desc': 'Frame synchronization'},
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{'id': 'clk', 'name': 'BIT_CLK', 'desc': 'Data bits clock'},
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)
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optional_channels = (
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{'id': 'out', 'name': 'SDATA_OUT', 'desc': 'Data output'},
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{'id': 'in', 'name': 'SDATA_IN', 'desc': 'Data input'},
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{'id': 'rst', 'name': 'RESET#', 'desc': 'Reset line'},
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)
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annotations = (
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('bit-out', 'Output bits'),
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('bit-in', 'Input bits'),
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('slot-out-raw', 'Output raw value'),
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('slot-out-tag', 'Output TAG'),
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('slot-out-cmd-addr', 'Output command address'),
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('slot-out-cmd-data', 'Output command data'),
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('slot-out-03', 'Output slot 3'),
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('slot-out-04', 'Output slot 4'),
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('slot-out-05', 'Output slot 5'),
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('slot-out-06', 'Output slot 6'),
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('slot-out-07', 'Output slot 7'),
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('slot-out-08', 'Output slot 8'),
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('slot-out-09', 'Output slot 9'),
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('slot-out-10', 'Output slot 10'),
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('slot-out-11', 'Output slot 11'),
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('slot-out-io-ctrl', 'Output I/O control'),
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('slot-in-raw', 'Input raw value'),
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('slot-in-tag', 'Input TAG'),
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('slot-in-sts-addr', 'Input status address'),
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('slot-in-sts-data', 'Input status data'),
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('slot-in-03', 'Input slot 3'),
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('slot-in-04', 'Input slot 4'),
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('slot-in-05', 'Input slot 5'),
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('slot-in-06', 'Input slot 6'),
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('slot-in-07', 'Input slot 7'),
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('slot-in-08', 'Input slot 8'),
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('slot-in-09', 'Input slot 9'),
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('slot-in-10', 'Input slot 10'),
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('slot-in-11', 'Input slot 11'),
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('slot-in-io-sts', 'Input I/O status'),
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# TODO: Add more annotation classes:
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# TAG: 'ready', 'valid', 'id', 'rsv'
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# CMD ADDR: 'r/w', 'addr', 'unused'
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# CMD DATA: 'data', 'unused'
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# 3-11: 'data', 'unused', 'double data'
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('warning', 'Warning'),
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('error', 'Error'),
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)
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annotation_rows = (
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('bits-out', 'Output bits', (Ann.BITS_OUT,)),
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('slots-out-raw', 'Output numbers', (Ann.SLOT_OUT_RAW,)),
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('slots-out', 'Output slots', (
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Ann.SLOT_OUT_TAG, Ann.SLOT_OUT_ADDR, Ann.SLOT_OUT_DATA,
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Ann.SLOT_OUT_03, Ann.SLOT_OUT_04, Ann.SLOT_OUT_05, Ann.SLOT_OUT_06,
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Ann.SLOT_OUT_07, Ann.SLOT_OUT_08, Ann.SLOT_OUT_09, Ann.SLOT_OUT_10,
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Ann.SLOT_OUT_11, Ann.SLOT_OUT_IO,)),
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('bits-in', 'Input bits', (Ann.BITS_IN,)),
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('slots-in-raw', 'Input numbers', (Ann.SLOT_IN_RAW,)),
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('slots-in', 'Input slots', (
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Ann.SLOT_IN_TAG, Ann.SLOT_IN_ADDR, Ann.SLOT_IN_DATA,
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Ann.SLOT_IN_03, Ann.SLOT_IN_04, Ann.SLOT_IN_05, Ann.SLOT_IN_06,
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Ann.SLOT_IN_07, Ann.SLOT_IN_08, Ann.SLOT_IN_09, Ann.SLOT_IN_10,
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Ann.SLOT_IN_11, Ann.SLOT_IN_IO,)),
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('warnings', 'Warnings', (Ann.WARN,)),
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('errors', 'Errors', (Ann.ERROR,)),
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)
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binary = (
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('frame-out', 'Frame bits, output data'),
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('frame-in', 'Frame bits, input data'),
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('slot-raw-out', 'Raw slot bits, output data'),
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('slot-raw-in', 'Raw slot bits, input data'),
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# TODO: Which (other) binary classes to implement?
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# - Are binary annotations per audio slot useful?
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# - Assume 20bit per slot, in 24bit units? Or assume 16bit
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# audio samples? Observe register access and derive width
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# of the audio data? Dump channels 3-11 or 1-12?
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)
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def putx(self, ss, es, cls, data):
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self.put(ss, es, self.out_ann, [cls, data])
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def putf(self, frombit, bitcount, cls, data):
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ss = self.frame_ss_list[frombit]
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es = self.frame_ss_list[frombit + bitcount]
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self.putx(ss, es, cls, data)
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def putb(self, frombit, bitcount, cls, data):
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ss = self.frame_ss_list[frombit]
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es = self.frame_ss_list[frombit + bitcount]
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self.put(ss, es, self.out_binary, [cls, data])
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def __init__(self):
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self.out_binary = None
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self.out_ann = None
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self.reset()
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def reset(self):
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self.frame_ss_list = None
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self.frame_slot_lens = [0, 16] + [16 + 20 * i for i in range(1, 13)]
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self.frame_total_bits = self.frame_slot_lens[-1]
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self.handle_slots = {
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0: self.handle_slot_00,
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1: self.handle_slot_01,
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2: self.handle_slot_02,
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}
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def start(self):
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if not self.out_binary:
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self.out_binary = self.register(srd.OUTPUT_BINARY)
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if not self.out_ann:
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self.out_ann = self.register(srd.OUTPUT_ANN)
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def metadata(self, key, value):
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if key == srd.SRD_CONF_SAMPLERATE:
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self.samplerate = value
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def bits_to_int(self, bits):
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# Convert MSB-first bit sequence to integer value.
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if not bits:
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return 0
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count = len(bits)
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value = sum([2 ** (count - 1 - i) for i in range(count) if bits[i]])
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return value
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def bits_to_bin_ann(self, bits):
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# Convert MSB-first bit sequence to binary annotation data.
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# It's assumed that the number of bits does not (in useful ways)
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# fit into an integer, and we need to create an array of bytes
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# from the data afterwards, anyway. Hence the separate routine
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# and the conversion of eight bits each.
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out = []
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count = len(bits)
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while count > 0:
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count -= 8
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by, bits = bits[:8], bits[8:]
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by = self.bits_to_int(by)
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out.append(by)
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out = bytes(out)
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return out
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def int_to_nibble_text(self, value, bitcount):
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# Convert number to hex digits for given bit count.
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digits = (bitcount + 3) // 4
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text = '{{:0{:d}x}}'.format(digits).format(value)
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return text
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def get_bit_field(self, data, size, off, count):
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shift = size - off - count
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data >>= shift
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mask = (1 << count) - 1
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data &= mask
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return data
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def flush_frame_bits(self):
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# Flush raw frame bits to binary annotation.
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anncls = Ann.BIN_FRAME_OUT
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data = self.frame_bits_out[:]
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count = len(data)
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data = self.bits_to_bin_ann(data)
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self.putb(0, count, anncls, data)
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anncls = Ann.BIN_FRAME_IN
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data = self.frame_bits_in[:]
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count = len(data)
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data = self.bits_to_bin_ann(data)
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self.putb(0, count, anncls, data)
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def start_frame(self, ss):
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# Mark the start of a frame.
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if self.frame_ss_list:
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# Flush bits if we had a frame before the frame which is
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# starting here.
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self.flush_frame_bits()
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self.frame_ss_list = [ss]
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self.frame_bits_out = []
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self.frame_bits_in = []
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self.frame_slot_data_out = []
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self.frame_slot_data_in = []
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self.have_slots = {True: None, False: None}
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def handle_slot_dummy(self, slotidx, bitidx, bitcount, is_out, data):
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# Handle slot x, default/fallback handler.
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# Only process data of slots 1-12 when slot 0 says "valid".
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if not self.have_slots[is_out]:
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return
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if not self.have_slots[is_out][slotidx]:
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return
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# Emit a naive annotation with just the data bits that we saw
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# for the slot (hex nibbles for density). For audio data this
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# can be good enough. Slots with special meaning should not end
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# up calling the dummy handler.
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text = self.int_to_nibble_text(data, bitcount)
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anncls = Ann.SLOT_OUT_TAG if is_out else Ann.SLOT_IN_TAG
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self.putf(bitidx, bitcount, anncls + slotidx, [text])
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# Emit binary output for the data that is contained in slots
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# which end up calling the default handler. This transparently
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# should translate to "the slots with audio data", as other
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# slots which contain management data should have their specific
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# handler routines. In the present form, this approach might be
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# good enough to get a (header-less) audio stream for typical
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# setups where only line-in or line-out are in use.
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#
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# TODO: Improve this early prototype implementation. For now the
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# decoder just exports the upper 16 bits of each audio channel
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# that happens to be valid. For an improved implementation, it
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# either takes user provided specs or more smarts like observing
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# register access (if the capture includes it).
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anncls = Ann.BIN_SLOT_RAW_OUT if is_out else Ann.BIN_SLOT_RAW_IN
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data_bin = data >> 4
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data_bin &= 0xffff
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data_bin = data_bin.to_bytes(2, byteorder = 'big')
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self.putb(bitidx, bitcount, anncls, data_bin)
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def handle_slot_00(self, slotidx, bitidx, bitcount, is_out, data):
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# Handle slot 0, TAG.
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slotpos = self.frame_slot_lens[slotidx]
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fieldoff = 0
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anncls = Ann.SLOT_OUT_TAG if is_out else Ann.SLOT_IN_TAG
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fieldlen = 1
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ready = self.get_bit_field(data, bitcount, fieldoff, fieldlen)
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text = ['READY: 1', 'READY', 'RDY', 'R'] if ready else ['ready: 0', 'rdy', '-']
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self.putf(slotpos + fieldoff, fieldlen, anncls, text)
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fieldoff += fieldlen
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fieldlen = 12
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valid = self.get_bit_field(data, bitcount, fieldoff, fieldlen)
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text = ['VALID: {:3x}'.format(valid), '{:3x}'.format(valid)]
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self.putf(slotpos + fieldoff, fieldlen, anncls, text)
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have_slots = [True] + [False] * 12
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for idx in range(12):
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have_slots[idx + 1] = bool(valid & (1 << (11 - idx)))
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self.have_slots[is_out] = have_slots
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fieldoff += fieldlen
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fieldlen = 1
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rsv = self.get_bit_field(data, bitcount, fieldoff, fieldlen)
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if rsv != 0:
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text = ['reserved bit error', 'rsv error', 'rsv']
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self.putf(slotpos + fieldoff, fieldlen, Ann.ERROR, text)
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fieldoff += fieldlen
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# TODO: Will input slot 0 have a Codec ID, or 3 reserved bits?
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fieldlen = 2
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codec = self.get_bit_field(data, bitcount, fieldoff, fieldlen)
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text = ['CODEC: {:1x}'.format(codec), '{:1x}'.format(codec)]
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self.putf(slotpos + fieldoff, fieldlen, anncls, text)
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fieldoff += fieldlen
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def handle_slot_01(self, slotidx, bitidx, bitcount, is_out, data):
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# Handle slot 1, command/status address.
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slotpos = self.frame_slot_lens[slotidx]
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if not self.have_slots[is_out]:
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return
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if not self.have_slots[is_out][slotidx]:
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return
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fieldoff = 0
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anncls = Ann.SLOT_OUT_TAG if is_out else Ann.SLOT_IN_TAG
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anncls += slotidx
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fieldlen = 1
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if is_out:
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is_read = self.get_bit_field(data, bitcount, fieldoff, fieldlen)
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text = ['READ', 'RD', 'R'] if is_read else ['WRITE', 'WR', 'W']
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self.putf(slotpos + fieldoff, fieldlen, anncls, text)
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# TODO: Check for the "atomic" constraint? Some operations
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# involve address _and_ data, which cannot be spread across
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# several frames. Slot 0 and 1 _must_ be provided within the
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# same frame (the test should occur in the handler for slot
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# 2 of course, in slot 1 we don't know what will follow).
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else:
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rsv = self.get_bit_field(data, bitcount, fieldoff, fieldlen)
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if rsv != 0:
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text = ['reserved bit error', 'rsv error', 'rsv']
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self.putf(slotpos + fieldoff, fieldlen, Ann.ERROR, text)
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fieldoff += fieldlen
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fieldlen = 7
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regaddr = self.get_bit_field(data, bitcount, fieldoff, fieldlen)
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# TODO: Present 0-63 or 0-126 as the address of the 16bit register?
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text = ['ADDR: {:2x}'.format(regaddr), '{:2x}'.format(regaddr)]
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self.putf(slotpos + fieldoff, fieldlen, anncls, text)
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if regaddr & 0x01:
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text = ['odd register address', 'odd reg addr', 'odd addr', 'odd']
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self.putf(slotpos + fieldoff, fieldlen, Ann.ERROR, text)
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fieldoff += fieldlen
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# Strictly speaking there are 10 data request bits and 2 reserved
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# bits for input slots, and 12 reserved bits for output slots. We
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# test for 10 and 2 bits, to simplify the logic. Only in case of
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# non-zero reserved bits for outputs this will result in "a little
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# strange" an annotation. This is a cosmetic issue, we don't mind.
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fieldlen = 10
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reqdata = self.get_bit_field(data, bitcount, fieldoff, fieldlen)
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if is_out and reqdata != 0:
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text = ['reserved bit error', 'rsv error', 'rsv']
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self.putf(slotpos + fieldoff, fieldlen, Ann.ERROR, text)
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if not is_out:
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text = ['REQ: {:3x}'.format(reqdata), '{:3x}'.format(reqdata)]
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self.putf(slotpos + fieldoff, fieldlen, anncls, text)
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fieldoff += fieldlen
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fieldlen = 2
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rsv = self.get_bit_field(data, bitcount, fieldoff, fieldlen)
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if rsv != 0:
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text = ['reserved bit error', 'rsv error', 'rsv']
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self.putf(slotpos + fieldoff, fieldlen, Ann.ERROR, text)
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fieldoff += fieldlen
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def handle_slot_02(self, slotidx, bitidx, bitcount, is_out, data):
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# Handle slot 2, command/status data.
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slotpos = self.frame_slot_lens[slotidx]
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if not self.have_slots[is_out]:
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return
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if not self.have_slots[is_out][slotidx]:
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return
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fieldoff = 0
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anncls = Ann.SLOT_OUT_TAG if is_out else Ann.SLOT_IN_TAG
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anncls += slotidx
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fieldlen = 16
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rwdata = self.get_bit_field(data, bitcount, fieldoff, fieldlen)
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# TODO: Check for zero output data when the operation is a read.
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# TODO: Check for the "atomic" constraint.
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text = ['DATA: {:4x}'.format(rwdata), '{:4x}'.format(rwdata)]
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self.putf(slotpos + fieldoff, fieldlen, anncls, text)
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fieldoff += fieldlen
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fieldlen = 4
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rsv = self.get_bit_field(data, bitcount, fieldoff, fieldlen)
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if rsv != 0:
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text = ['reserved bits error', 'rsv error', 'rsv']
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self.putf(slotpos + fieldoff, fieldlen, Ann.ERROR, text)
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fieldoff += fieldlen
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# TODO: Implement other slots.
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# - 1: cmd/status addr (check status vs command)
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# - 2: cmd/status data (check status vs command)
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# - 3-11: audio out/in
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# - 12: io control/status (modem GPIO(?))
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def handle_slot(self, slotidx, data_out, data_in):
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# Process a received slot of a frame.
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func = self.handle_slots.get(slotidx, self.handle_slot_dummy)
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bitidx = self.frame_slot_lens[slotidx]
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bitcount = self.frame_slot_lens[slotidx + 1] - bitidx
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if data_out is not None:
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func(slotidx, bitidx, bitcount, True, data_out)
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if data_in is not None:
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func(slotidx, bitidx, bitcount, False, data_in)
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def handle_bits(self, ss, es, bit_out, bit_in):
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# Process a received pair of bits.
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# Emit the bits' annotations. Only interpret the data when we
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# are in a frame (have seen the start of the frame, and don't
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# exceed the expected number of bits in a frame).
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if bit_out is not None:
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self.putx(ss, es, Ann.BITS_OUT, ['{:d}'.format(bit_out)])
|
|
if bit_in is not None:
|
|
self.putx(ss, es, Ann.BITS_IN, ['{:d}'.format(bit_in)])
|
|
if self.frame_ss_list is None:
|
|
return
|
|
self.frame_ss_list.append(es)
|
|
have_len = len(self.frame_ss_list) - 1
|
|
if have_len > self.frame_total_bits:
|
|
return
|
|
|
|
# Accumulate the bits within the frame, until one slot of the
|
|
# frame has become available.
|
|
slot_idx = 0
|
|
if bit_out is not None:
|
|
self.frame_bits_out.append(bit_out)
|
|
slot_idx = len(self.frame_slot_data_out)
|
|
if bit_in is not None:
|
|
self.frame_bits_in.append(bit_in)
|
|
slot_idx = len(self.frame_slot_data_in)
|
|
want_len = self.frame_slot_lens[slot_idx + 1]
|
|
if have_len != want_len:
|
|
return
|
|
prev_len = self.frame_slot_lens[slot_idx]
|
|
|
|
# Convert bits to integer values. This shall simplify extraction
|
|
# of bit fields in multiple other locations.
|
|
slot_data_out = None
|
|
if bit_out is not None:
|
|
slot_bits = self.frame_bits_out[prev_len:]
|
|
slot_data = self.bits_to_int(slot_bits)
|
|
self.frame_slot_data_out.append(slot_data)
|
|
slot_data_out = slot_data
|
|
slot_data_in = None
|
|
if bit_in is not None:
|
|
slot_bits = self.frame_bits_in[prev_len:]
|
|
slot_data = self.bits_to_int(slot_bits)
|
|
self.frame_slot_data_in.append(slot_data)
|
|
slot_data_in = slot_data
|
|
|
|
# Emit simple annotations for the integer values, until upper
|
|
# layer decode stages will be implemented.
|
|
slot_len = have_len - prev_len
|
|
slot_ss = self.frame_ss_list[prev_len]
|
|
slot_es = self.frame_ss_list[have_len]
|
|
if slot_data_out is not None:
|
|
slot_text = self.int_to_nibble_text(slot_data_out, slot_len)
|
|
self.putx(slot_ss, slot_es, Ann.SLOT_OUT_RAW, [slot_text])
|
|
if slot_data_in is not None:
|
|
slot_text = self.int_to_nibble_text(slot_data_in, slot_len)
|
|
self.putx(slot_ss, slot_es, Ann.SLOT_IN_RAW, [slot_text])
|
|
|
|
self.handle_slot(slot_idx, slot_data_out, slot_data_in)
|
|
|
|
def decode(self):
|
|
have_sdo = self.has_channel(Pins.SDATA_OUT)
|
|
have_sdi = self.has_channel(Pins.SDATA_IN)
|
|
if not have_sdo and not have_sdi:
|
|
raise ChannelError('Either SDATA_OUT or SDATA_IN (or both) are required.')
|
|
have_reset = self.has_channel(Pins.RESET)
|
|
|
|
# Data is sampled at falling CLK edges. Annotations need to span
|
|
# the period between rising edges. SYNC rises one cycle _before_
|
|
# the start of a frame. Grab the earliest SYNC sample we can get
|
|
# and advance to the start of a bit time. Then keep getting the
|
|
# samples and the end of all subsequent bit times.
|
|
prev_sync = [None, None, None]
|
|
(sync, bit_clk, sdata_out, sdata_in, reset) = self.wait({Pins.BIT_CLK: 'e'})
|
|
if bit_clk == 0:
|
|
prev_sync[-1] = sync
|
|
(sync, bit_clk, sdata_out, sdata_in, reset) = self.wait({Pins.BIT_CLK: 'r'})
|
|
bit_ss = self.samplenum
|
|
while True:
|
|
(sync, bit_clk, sdata_out, sdata_in, reset) = self.wait({Pins.BIT_CLK: 'f'})
|
|
prev_sync.pop(0)
|
|
prev_sync.append(sync)
|
|
self.wait({Pins.BIT_CLK: 'r'})
|
|
if prev_sync[0] == 0 and prev_sync[1] == 1:
|
|
self.start_frame(bit_ss)
|
|
self.handle_bits(bit_ss, self.samplenum,
|
|
sdata_out if have_sdo else None,
|
|
sdata_in if have_sdi else None)
|
|
bit_ss = self.samplenum
|