hulk
8e91e661f1
背景: 用户接非 DLPilot 协议设备(COM25)开解析模式接收区一片空白——_dispatch_rx 在解析模式只上抛完整合法帧, 不成帧字节(纯文本日志/别的协议/波特率不符乱码)被 FrameParser 重同步时静默丢弃。用户明确定位: 首先是基础串口调试工具, 自定义协议解析是附加项, 附加能力不得影响本体功能。 修复: protocol.py FrameParser 丢弃字节累积进 garbage(新增 drain_garbage(), feed() 返回值不变); link.py 新增 on_garbage(data, ts) 回调, 每批无条件 drain(未接回调也不累积); main.py 把 on_garbage 并入 raw 事件与透传行同格式显示, 解析协议帧开关补 tooltip, 版本 0.1.2。半帧前缀扣留语义有意保留(可能补全成真帧, 至多扣一个前缀长度)。 自检: selftest 8b +10 项(纯文本全透出/噪声+帧+尾字节/坏CRC帧字节全透出/半帧头扣留补全), loop 3b +3 项, gui 5b +2 项; 全量 67+21+68 项 PASS; exe 已重建。README/AGENTS.md(不变量 5a) 同步。
467 lines
18 KiB
Python
467 lines
18 KiB
Python
#!/usr/bin/env python3
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# -*- coding: utf-8 -*-
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"""
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SerialAssistant 串口协议模块(纯标准库, 帧构成可定制)
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======================================================
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帧由"构成令牌序列"定义(默认与 DLPilot 光机 RS485 协议完全一致):
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HDR ID LEN PAYLOAD CRC -> 包头 + 板ID + LEN + payload + CRC
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LEN = payload 字节数(口径可选, 见 LEN_SEMS), 默认即"包长对应 payload 长度"
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令牌: HDR=包头 ID=板ID LEN=长度 PAYLOAD=载荷 CRC=校验(必须最后),
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其余 1~2 位十六进制(如 AA 55)为固定字面量字节(双字节同步头)。
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约束: LEN/PAYLOAD/CRC 恰好各一次; LEN 前至少一个 HDR 或字面量(同步定界用)。
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同一布局收发共用, 仅包头值分方向(TX=tx_hdr / RX=rx_hdr); ID 在 RX 侧
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按上游语义多为响应 TYPE 码, 解析时不校验、原样透出(Frame.code, 可为 None)。
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CRC 算法(2 字节算法在线上的字节序: MODBUS 低位在前, 其余高位在前):
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SUM8 累加和取低 8 位(1 字节)
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CRC8 poly 0x07 init 0x00(1 字节, 标准校验值 check("123456789")=0xF4)
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CRC16_MODBUS poly 0x8005 反射 init 0xFFFF(2 字节, check=0x4B37)
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CRC16_XMODEM poly 0x1021 init 0x0000(2 字节, check=0x31C3)
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CRC16_CCITT poly 0x1021 init 0xFFFF(2 字节, check=0x29B1)
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CRC 覆盖范围(CRC_SCOPES, 按帧内位置定义, 任意布局通用):
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with_header 包头(第1字节)起至 CRC 前
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no_header 第 2 字节起至 CRC 前(DLPilot 默认)
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payload_only 仅 payload
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仅标准库; pyserial 只允许出现在 link.py。
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"""
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import collections
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import re
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import struct
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LEN_MAX = 255 # LEN 为单字节, payload 上限 255
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TYPE_NAMES = { # DLPilot/上游 protocols.md 的响应 TYPE 码语义, 用于 RX 译码显示
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0xF0: '成功',
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0xF1: 'CRC 校验错',
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0xF2: '包头错',
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0xF3: '板类型错',
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0xF4: '格式/缺参数',
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0xFD: '参数越界/读回复核不一致',
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0xFE: '未知命令',
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0xFF: '通用错误(含就绪门禁拒绝)',
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0xFA: '开光机通信失败',
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0xFB: '关光机通信失败',
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0xFC: '读回复核通信失败',
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}
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# --- CRC 实现(查表, 供高波特率下增量解析用) ---------------------------------
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def _table_crc8():
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tbl = []
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for b in range(256):
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c = b
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for _ in range(8):
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c = ((c << 1) ^ 0x07) & 0xFF if c & 0x80 else (c << 1) & 0xFF
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tbl.append(c)
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return tuple(tbl)
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def _table_crc16_msb():
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"""MSB-first 表(poly 0x1021, 用于 XMODEM/CCITT)"""
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tbl = []
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for b in range(256):
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c = (b << 8) & 0xFFFF
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for _ in range(8):
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c = ((c << 1) ^ 0x1021) & 0xFFFF if c & 0x8000 else (c << 1) & 0xFFFF
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tbl.append(c)
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return tuple(tbl)
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def _table_crc16_reflected():
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"""反射表(poly 0x8005 → 0xA001, 用于 MODBUS)"""
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tbl = []
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for b in range(256):
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c = b
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for _ in range(8):
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c = (c >> 1) ^ 0xA001 if c & 1 else c >> 1
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tbl.append(c)
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return tuple(tbl)
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_TAB_CRC8 = _table_crc8()
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_TAB_CRC16_MSB = _table_crc16_msb()
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_TAB_CRC16_REF = _table_crc16_reflected()
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def _sum8(data):
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return sum(data) & 0xFF
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def _crc8(data, _t=_TAB_CRC8):
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c = 0
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for b in data:
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c = _t[c ^ b]
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return c
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def _crc16_msb(data, init, _t=_TAB_CRC16_MSB):
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c = init
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for b in data:
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c = ((c << 8) & 0xFFFF) ^ _t[((c >> 8) ^ b) & 0xFF]
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return c
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def _crc16_xmodem(data):
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return _crc16_msb(data, 0x0000)
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def _crc16_ccitt(data):
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return _crc16_msb(data, 0xFFFF)
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def _crc16_modbus(data, _t=_TAB_CRC16_REF):
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c = 0xFFFF
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for b in data:
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c = (c >> 8) ^ _t[(c ^ b) & 0xFF]
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return c
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# name -> (CRC 字节数, 计算函数, 线上字节序: 'big'=高字节在前 / 'little'=低字节在前)
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CRC_ALGOS = {
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'SUM8': (1, _sum8, 'big'),
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'CRC8': (1, _crc8, 'big'),
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'CRC16_MODBUS': (2, _crc16_modbus, 'little'),
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'CRC16_XMODEM': (2, _crc16_xmodem, 'big'),
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'CRC16_CCITT': (2, _crc16_ccitt, 'big'),
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}
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CRC_ALGO_LABELS = { # 下拉框显示文本
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'SUM8': 'SUM8 累加和',
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'CRC8': 'CRC8 (poly 07)',
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'CRC16_MODBUS': 'CRC16 MODBUS',
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'CRC16_XMODEM': 'CRC16 XMODEM',
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'CRC16_CCITT': 'CRC16 CCITT-FALSE',
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}
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CRC_SCOPES = ('with_header', 'no_header', 'payload_only')
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CRC_SCOPE_LABELS = {
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'with_header': '含包头(整帧不含CRC)',
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'no_header': '不含包头(跳过第1字节, DLPilot)',
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'payload_only': '仅 payload',
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}
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LEN_SEMS = ('payload', 'body', 'total')
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LEN_SEM_LABELS = { # LEN 字节的计数口径
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'payload': 'payload 长度(默认)',
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'body': '到帧尾(payload+CRC)',
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'total': '整帧(含包头)',
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}
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DEFAULT_LAYOUT = 'HDR ID LEN PAYLOAD CRC'
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_FRAME_TOKEN_RE = re.compile(r'^(?:0x)?([0-9A-Fa-f]{1,2})$')
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_KEYWORDS = {'HDR': 'hdr', 'ID': 'id', 'BOARD': 'id', 'LEN': 'len',
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'PAYLOAD': 'payload', 'DATA': 'payload', 'CRC': 'crc'}
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class FrameLayout:
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"""帧构成: 令牌序列(parse 文本而来), 供组帧与解析共用。
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tokens 元素: 'hdr'/'id'/'len'/'payload'/'crc' 或 ('lit', 字节值)。
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约束(parse 内校验): LEN/PAYLOAD/CRC 恰好各一次; CRC 必须最后;
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LEN 之前至少一个 HDR 或字面量(否则无同步定界); ID 最多一次。
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payload 之前的令牌都是 1 字节(CRC 在最后), 故 payload 字节偏移=payload_pos。
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"""
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def __init__(self, tokens):
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self.tokens = tuple(tokens)
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counts = collections.Counter(
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t if isinstance(t, str) else 'lit' for t in self.tokens)
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for key, cn in (('len', 'LEN'), ('payload', 'PAYLOAD'), ('crc', 'CRC')):
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if counts[key] != 1:
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raise ValueError(f'{cn} 必须恰好出现一次(当前 {counts[key]} 次)')
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if self.tokens[-1] != 'crc':
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raise ValueError('CRC 必须是最后一个令牌')
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if counts['id'] > 1:
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raise ValueError('ID 最多出现一次')
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self.len_pos = self.tokens.index('len')
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self.payload_pos = self.tokens.index('payload')
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id_positions = [i for i, t in enumerate(self.tokens) if t == 'id']
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self.id_pos = id_positions[0] if id_positions else None
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if not any(isinstance(t, tuple) or t == 'hdr'
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for t in self.tokens[:self.len_pos]):
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raise ValueError('LEN 之前需要至少一个 HDR 或十六进制字面量作同步头')
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@classmethod
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def parse(cls, text):
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"""'AA 55 ID LEN PAYLOAD CRC' 之类 -> FrameLayout; 非法抛 ValueError"""
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parts = [p for p in re.split(r'[\s,，;；]+', (text or '').strip()) if p]
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if not parts:
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raise ValueError('帧构成为空')
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tokens = []
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for p in parts:
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kw = _KEYWORDS.get(p.upper())
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if kw:
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tokens.append(kw)
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continue
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m = _FRAME_TOKEN_RE.match(p)
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if not m:
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raise ValueError(f'未知令牌 "{p}"(可用: HDR ID LEN PAYLOAD CRC '
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f'或 0~FF 十六进制字面量)')
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tokens.append(('lit', int(m.group(1), 16)))
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return cls(tokens)
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# --- 尺寸(依赖 CRC 字节数, 由 ProtoConfig 传参) ---
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def rest_size(self, crc_size):
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"""payload 之后的字节数(ID/HDR/字面量 + CRC)"""
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return crc_size + len(self.tokens) - self.payload_pos - 2
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def total_size(self, payload_len, crc_size):
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# payload 之前的令牌都是 1 字节, payload 字节偏移即 payload_pos
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return self.payload_pos + payload_len + self.rest_size(crc_size)
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def len_extra(self, len_sem, crc_size):
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"""LEN 字节值 = payload_len + 该口径下的附加字节数"""
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if len_sem == 'body':
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return self.rest_size(crc_size)
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if len_sem == 'total':
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return self.payload_pos + self.rest_size(crc_size)
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return 0
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Frame = collections.namedtuple('Frame', 'code payload raw')
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"""code=ID 位置字节(RX 侧多为响应 TYPE 码; 布局无 ID 时为 None),
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payload=原始字节, raw=整帧含 CRC"""
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class ProtoConfig:
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"""协议配置: 帧构成(FrameLayout) + 包头(TX/RX)/板ID/LEN 口径/CRC 算法与覆盖"""
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def __init__(self, tx_hdr=0xD5, rx_hdr=0xB5, board=0x01,
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crc_algo='SUM8', crc_scope='no_header',
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layout=None, len_sem='payload'):
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for name, v in (('tx_hdr', tx_hdr), ('rx_hdr', rx_hdr), ('board', board)):
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if not 0 <= int(v) <= 0xFF:
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raise ValueError(f'{name} 超出 0~255: {v}')
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if crc_algo not in CRC_ALGOS:
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raise ValueError(f'未知 CRC 算法: {crc_algo}')
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if crc_scope not in CRC_SCOPES:
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raise ValueError(f'未知 CRC 覆盖范围: {crc_scope}')
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if len_sem not in LEN_SEMS:
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raise ValueError(f'未知 LEN 口径: {len_sem}')
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self.tx_hdr, self.rx_hdr, self.board = int(tx_hdr), int(rx_hdr), int(board)
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self.crc_algo, self.crc_scope = crc_algo, crc_scope
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self.len_sem = len_sem
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self.layout = layout if layout is not None else FrameLayout.parse(DEFAULT_LAYOUT)
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@property
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def crc_size(self):
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return CRC_ALGOS[self.crc_algo][0]
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# --- CRC ---
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def compute_crc(self, nocrc_frame, payload_len):
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"""对不含 CRC 的整帧按覆盖范围切片算 CRC 值(切片按位置定义, 任意布局通用)"""
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_size, fn, _order = CRC_ALGOS[self.crc_algo]
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if self.crc_scope == 'no_header':
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region = nocrc_frame[1:]
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elif self.crc_scope == 'payload_only':
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po = self.layout.payload_pos
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region = nocrc_frame[po:po + payload_len]
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else:
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region = nocrc_frame
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return fn(region)
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def encode_crc(self, value):
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"""CRC 值 -> 线上字节(2 字节算法按算法约定字节序)"""
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size, _fn, order = CRC_ALGOS[self.crc_algo]
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if size == 1:
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return bytes((value & 0xFF,))
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hi, lo = (value >> 8) & 0xFF, value & 0xFF
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return bytes((hi, lo)) if order == 'big' else bytes((lo, hi))
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# --- 组帧 ---
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def build_frame(self, payload):
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"""payload bytes -> 完整帧 bytes; 空载荷允许(LEN=0), 超限抛 ValueError"""
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payload = bytes(payload)
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if len(payload) > LEN_MAX:
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raise ValueError(f'payload 超长(>{LEN_MAX} 字节)')
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cs = self.crc_size
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len_val = len(payload) + self.layout.len_extra(self.len_sem, cs)
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if len_val > LEN_MAX:
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raise ValueError(f'LEN 字节溢出(={len_val}>255), 检查帧构成与 LEN 口径')
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parts = []
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for tok in self.layout.tokens:
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if tok == 'crc':
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continue # CRC 最后, 跳过待拼
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if tok == 'hdr':
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parts.append(bytes((self.tx_hdr,)))
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elif tok == 'id':
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parts.append(bytes((self.board,)))
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elif tok == 'len':
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parts.append(bytes((len_val,)))
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elif tok == 'payload':
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parts.append(payload)
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else:
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parts.append(bytes((tok[1],)))
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nocrc = b''.join(parts)
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return nocrc + self.encode_crc(self.compute_crc(nocrc, len(payload)))
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# --- 校验与拆帧 ---
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def _plen_of(self, raw):
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"""从整帧 LEN 字节解出 payload 长度; 非法(负值)返回 None"""
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plen = raw[self.layout.len_pos] - self.layout.len_extra(self.len_sem, self.crc_size)
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return plen if plen >= 0 else None
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def verify_frame(self, raw):
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"""整帧(含 CRC)校验: 长度与 LEN 口径自洽 + CRC 匹配"""
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cs = self.crc_size
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if len(raw) < self.layout.len_pos + 1 + cs:
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return False
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plen = self._plen_of(raw)
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if plen is None or len(raw) != self.layout.total_size(plen, cs):
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return False
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return self.encode_crc(self.compute_crc(raw[:-cs], plen)) == raw[-cs:]
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def parse_frame(self, raw):
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"""整帧 -> Frame(不校验 CRC, 调用方先用 verify_frame); 长度不符抛 ValueError"""
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cs = self.crc_size
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plen = self._plen_of(raw)
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if plen is None or len(raw) != self.layout.total_size(plen, cs):
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raise ValueError('帧长与 LEN 口径不符')
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po = self.layout.payload_pos
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code = raw[self.layout.id_pos] if self.layout.id_pos is not None else None
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return Frame(code, raw[po:po + plen], bytes(raw))
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class FrameParser:
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"""增量字节流 -> 完整帧: 前缀令牌逐位对齐(帧头/字面量, ID 为通配) + LEN 定长
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+ CRC 校验; 任一处失配丢 1 字节重新同步。LEN 值经口径换算后即 payload 长度,
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负值视为伪帧头逐出 —— 伪帧头最多滞留一帧即被逐出重同步, 对调试工具可接受。
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丢弃字节不销毁: 累积进 self.garbage, 由上层 drain_garbage() 取走透出 ——
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本工具首先是串口助手, 协议解析是附加层, 不成帧的字节也必须可见。
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(仅匹配上前缀、还在等后续字节的"半帧"缓冲不算垃圾, 可能补全成真帧)
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"""
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def __init__(self, cfg):
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self.cfg = cfg
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lay = cfg.layout
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cs = cfg.crc_size
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# LEN 之前的前缀令牌: (帧内位置, 期望字节|None=通配); hdr 按 RX 包头匹配
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self._prefix = []
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for pos, tok in enumerate(lay.tokens[:lay.len_pos]):
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exp = None
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if tok == 'hdr':
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exp = cfg.rx_hdr
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elif isinstance(tok, tuple):
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exp = tok[1]
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self._prefix.append((pos, exp))
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self._len_pos = lay.len_pos
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self._extra = lay.len_extra(cfg.len_sem, cs)
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self._buf = bytearray()
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self.garbage = bytearray() # 重同步丢弃的非帧字节(调用方定期取走)
|
||
|
||
def clear(self):
|
||
self._buf.clear()
|
||
self.garbage.clear()
|
||
|
||
def drain_garbage(self):
|
||
"""取走累积的非帧字节(bytes)并清空; 解析模式不吞数据的取数入口"""
|
||
out = bytes(self.garbage)
|
||
self.garbage.clear()
|
||
return out
|
||
|
||
def _drop_head(self):
|
||
"""丢缓冲首字节重同步; 丢弃字节记入 garbage(可能正是用户要看的输出)"""
|
||
self.garbage.append(self._buf[0])
|
||
del self._buf[:1]
|
||
|
||
def _aligned(self):
|
||
"""把缓冲对齐到前缀匹配; 字节不足且已匹配部分则保持等待(返回 True),
|
||
失配丢 1 字节重试, 缓冲耗尽返回 False"""
|
||
buf = self._buf
|
||
while True:
|
||
for pos, exp in self._prefix:
|
||
if pos >= len(buf):
|
||
return True # 已匹配部分全对, 等更多字节
|
||
if exp is not None and buf[pos] != exp:
|
||
break # 失配 -> 丢 1 字节
|
||
else:
|
||
return True
|
||
self._drop_head()
|
||
if not buf:
|
||
return False
|
||
|
||
def feed(self, data):
|
||
"""喂入新收到的字节, 返回本次解析出的完整 Frame 列表"""
|
||
self._buf += bytes(data)
|
||
cfg, frames = self.cfg, []
|
||
while self._aligned() and self._buf:
|
||
if len(self._buf) < self._len_pos + 1:
|
||
break # LEN 字节未到齐
|
||
plen = self._buf[self._len_pos] - self._extra
|
||
if plen < 0: # LEN 为负 -> 伪帧头, 逐出重同步
|
||
self._drop_head()
|
||
continue
|
||
total = cfg.layout.total_size(plen, cfg.crc_size)
|
||
if len(self._buf) < total:
|
||
break # 整帧未收齐
|
||
raw = bytes(self._buf[:total])
|
||
if cfg.verify_frame(raw):
|
||
frames.append(cfg.parse_frame(raw))
|
||
del self._buf[:total]
|
||
else:
|
||
self._drop_head() # CRC 失配 -> 丢帧头重同步
|
||
return frames
|
||
|
||
|
||
# --- payload 数值提取(曲线通道用) --------------------------------------------
|
||
|
||
BIN_FORMATS = { # fmt -> (struct 格式, 字节数)
|
||
'u8': ('B', 1), 's8': ('b', 1),
|
||
'u16be': ('>H', 2), 'u16le': ('<H', 2),
|
||
's16be': ('>h', 2), 's16le': ('<h', 2),
|
||
'u32be': ('>I', 4), 'u32le': ('<I', 4),
|
||
's32be': ('>i', 4), 's32le': ('<i', 4),
|
||
'f32be': ('>f', 4), 'f32le': ('<f', 4),
|
||
}
|
||
NUM_RE = re.compile(r'-?\d+(?:\.\d+)?')
|
||
|
||
|
||
def extract_value(payload, mode, *, offset=0, fmt='u16be', index=1,
|
||
pattern=r'(?<=:)\d+', scale=1.0):
|
||
"""从 payload 提取一个数值(已乘 scale); 提取失败返回 None。
|
||
|
||
bin 二进制定长提取: offset 起, 按 fmt(BIN_FORMATS 键)解
|
||
num ASCII 文本第 index(1 基)个数字, 如 'okTL:246' -> 246
|
||
re 正则第 1 捕获组(无组则整体), 如 '(?<=:)(\\d+)'
|
||
"""
|
||
payload = bytes(payload)
|
||
try:
|
||
if mode == 'bin':
|
||
if fmt not in BIN_FORMATS:
|
||
return None
|
||
sfmt, size = BIN_FORMATS[fmt]
|
||
if offset < 0 or len(payload) < offset + size:
|
||
return None
|
||
value = struct.unpack(sfmt, payload[offset:offset + size])[0]
|
||
elif mode == 'num':
|
||
nums = NUM_RE.findall(payload.decode('ascii', 'replace'))
|
||
if not 1 <= index <= len(nums):
|
||
return None
|
||
value = float(nums[index - 1])
|
||
elif mode == 're':
|
||
m = re.search(pattern, payload.decode('ascii', 'replace'))
|
||
if not m:
|
||
return None
|
||
value = float(m.group(1) if m.groups() else m.group(0))
|
||
else:
|
||
return None
|
||
except (ValueError, re.error):
|
||
return None
|
||
return value * scale
|
||
|
||
|
||
def hexs(data):
|
||
"""bytes -> 'AA BB CC' 大写 hex, 日志统一格式"""
|
||
return bytes(data).hex(' ').upper()
|
||
|
||
|
||
def clean_text(s):
|
||
"""控制字符 -> '·': 二进制按 ASCII 解出的 NUL 等会污染日志行,
|
||
且 Windows 剪贴板遇 NUL 直接截断复制内容(DLPilot 同源教训)"""
|
||
return ''.join(c if ord(c) >= 0x20 and ord(c) != 0x7F else '·' for c in s)
|