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comparison python/hexfile.py @ 104:ed230e947dc6

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Added hexviewer
author windel
date Sun, 30 Dec 2012 22:31:55 +0100
parents
children d3dccf12ca88
comparison
equal deleted inserted replaced
103:28a35161ef23 104:ed230e947dc6
1 import os
2
3 class HexFileException(Exception):
4 pass
5
6 def parseHexLine(line):
7 """ Parses a hexfile line into three parts """
8 line = line[1:] # Remove ':'
9 nums = bytes.fromhex(line)
10 bytecount = nums[0]
11 if len(nums) != bytecount + 5:
12 raise HexFileException('byte count field incorrect')
13 crc = sum(nums)
14 if (crc & 0xFF) != 0:
15 raise HexFileException('crc incorrect')
16 address = nums[1] * 256 + nums[2]
17 typ = nums[3]
18 data = nums[4:-1]
19 return (address, typ, data)
20
21 class HexFile:
22 """ Represents an intel hexfile """
23 def __init__(self, filename=None):
24 self.regions = []
25 self.startAddress = 0
26 self.filename = None
27 if filename:
28 self.load(filename)
29
30 def load(self, filename):
31 with open(filename, 'r') as f:
32 endOfFile = False
33 offset = 0
34 startAddress = 0
35 curAddress = 0
36 curData = bytearray()
37 for line in f:
38 line = line.strip() # Strip spaces and newlines
39 if not line: continue # Skip empty lines
40 if line[0] != ':': continue # Skip lines that do not start with a ':'
41 if endOfFile: raise HexFileException('hexfile line after end of file record')
42 address, typ, data = parseHexLine(line)
43 if typ == 0x0: # Data record
44 address += offset # Fix address with offset
45 # Append data
46 if address == curAddress:
47 curData += data
48 curAddress += len(data)
49 else:
50 if curData:
51 self.regions.append(HexFileRegion(startAddress, bytes(curData)))
52 startAddress = address
53 curAddress = address + len(data)
54 curData = bytearray(data)
55 elif typ == 0x4: # Extended linear address record
56 offset = ((data[0] << 8) + data[1]) << 16
57 elif typ == 0x1: # End of file record
58 if len(data) != 0:
59 raise HexFileException('end of file record must contain no data')
60 endOfFile = True
61 elif typ == 0x5: # Start address record (where IP goes after loading)
62 self.startAddress = (data[0] << 24) + (data[1] << 16) + (data[2] << 8) + data[3]
63 else:
64 raise HexFileException('record type {0} not implemented'.format(typ))
65 print(hex(address), typ, data)
66 # After all lines:
67 if curData:
68 self.regions.append(HexFileRegion(startAddress, bytes(curData)))
69 # Store the filename:
70 self.filename = filename
71 def __repr__(self):
72 i = []
73 i.append(super().__repr__())
74 i.append('Start address {0}'.format(hex(self.startAddress)))
75 i.append('Filename: {0}'.format(self.filename))
76 for r in self.regions:
77 i.append(str(r))
78 return os.linesep.join(i)
79 def save(self, filename):
80 with open(filename, 'w') as f:
81 for line in f:
82 pass
83
84 class HexFileRegion:
85 def __init__(self, address, data = bytes()):
86 self.address = address
87 self.data = data
88 def __repr__(self):
89 return 'Region at 0x{0:X} of {1} bytes'.format(self.address, len(self.data))
90
91 if __name__ == '__main__':
92 h = HexFile()
93 print(h)
94 """ Test hexfile implementation with some hexfile """
95 h1 = HexFile('audio.hex')
96 print(h1)
97