Files
StreamLens/analyzer/protocols/decoders/uart.py
2025-07-28 08:14:15 -04:00

69 lines
2.3 KiB
Python

"""
UART Data decoder for Chapter 10 data types
Supports UART Data Format 0 (0x50)
"""
import struct
from typing import Dict, Any, Optional
from .base import DataTypeDecoder, DecodedPayload
class UARTDecoder(DataTypeDecoder):
"""Decoder for UART Data type (0x50)"""
def __init__(self):
super().__init__()
self.data_type_base = 0x50
self.data_type_name = "UART Data"
self.supported_formats = [0x50]
def can_decode(self, data_type: int) -> bool:
return data_type == 0x50
def get_data_type_name(self, data_type: int) -> str:
return "UART Data Format 0"
def decode(self, payload: bytes, ch10_header: Dict[str, Any]) -> Optional[DecodedPayload]:
"""Decode UART payload"""
decoded_data = {}
errors = []
# Parse IPH
iph = self._parse_intra_packet_header(payload)
if iph:
decoded_data.update(iph)
data_start = iph['data_start']
else:
data_start = 0
errors.append("Failed to parse intra-packet header")
# Parse UART data
if data_start < len(payload):
uart_data = payload[data_start:]
decoded_data['uart_data_length'] = len(uart_data)
# Try to decode as text
try:
text_data = uart_data.decode('ascii', errors='ignore')
decoded_data['ascii_data'] = text_data
decoded_data['printable_chars'] = sum(1 for c in text_data if c.isprintable())
except:
decoded_data['ascii_decode_failed'] = True
# Raw hex representation
decoded_data['raw_hex'] = uart_data[:256].hex() # First 256 bytes
# Basic statistics
decoded_data['null_count'] = uart_data.count(0)
decoded_data['cr_count'] = uart_data.count(ord('\r'))
decoded_data['lf_count'] = uart_data.count(ord('\n'))
return DecodedPayload(
data_type=0x50,
data_type_name="UART Data Format 0",
format_version=0,
decoded_data=decoded_data,
raw_payload=payload,
errors=errors,
metadata={'decoder': 'UARTDecoder'}
)