With a bit of "observing" with IDA and Udis86 and also a bit of Python hacking, I was able to determine the checksum scheme used with the .bin
and .bsc
files.
Here's a little Python code (from within 'ipython') that shows how to generate the required checksum:
In [1]: f=open('NLEN2.bin','r')
In [2]: s=f.read()
In [3]: from arraymodule import *
In [4]: my_int8s=[b for b in array('b',s)]
In [5]: my_int8s[:10]
Out[5]: [2, -103, -110, 0, -128, -128, 0, 10, -125, 10]
In [6]: my_checksum=sum(my_int8s)%(2**32)
In [7]: my_checksum
Out[7]: 4280806306L
N.B.: The program appeared to sum exactly 524288 bytes in each .bin
file.
N.B.: The Python above could be made faster/smaller if desired.
EDIT
Here's the "script" without the ipython line numbers, etc., and hopefully works on your Windows platform.
f=open('NLEN2.bin','rb')
s=f.read()
from array import *
my_int8s=[b for b in array('b',s)]
my_checksum=sum(my_int8s)%(2**32)
print("Checksum: %d\n" % my_checksum)