Extract and plot data from Vice C64 snapshots

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###  Extract and plot data from Vice C64 snapshots                          ###
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import matplotlib.pyplot as plt

Filename            = "../vice-snapshot.vsf"
DataIndex           = 0x1000
NumberOfEntries     = 128
WordLengthInBytes   = 2
DataSizeInBytes     = NumberOfEntries * WordLengthInBytes
IsSigned            = True

with open(Filename, 'rb') as f:
    viceSnapshot = f.read()

# Extract data from dump
C64MEMStringIndex = viceSnapshot.find(b'C64MEM')
RAMDumpIndex = C64MEMStringIndex + 26
RAMDump = viceSnapshot[RAMDumpIndex:RAMDumpIndex + pow(2, 16)]
data = RAMDump[DataIndex:DataIndex + DataSizeInBytes]

# Extract integers from data
data = [int.from_bytes(data[i : i + WordLengthInBytes], byteorder = 'little', signed = IsSigned)\
    for i in range(0, len(data), WordLengthInBytes)]

plt.plot(data)
plt.show()