bin2cas.py

#!/usr/bin/python
# -*- coding: latin-1 -*-

"""
    bin2cas.py
    ~~~~~~~~~~

    converter binary files to .cas used on CoCo2/drgaon 32 emulators like XRoar

    origin code from: http://pastebin.com/GCw1NAeY
    see: http://www.coco3.com/community/2010/12/converting-binary-files-to-coco2-cas-files/

    cleanup 2013 by Jens Diemer
"""

import os, sys

def hexvl(a_st):
    a_st = a_st.lower()
    tmpr = 0
    hx_st = "0123456789abcdef"
    hx_st = hx_st.lower()
    for i in range(0, len(a_st), 1):
        tmpr = (tmpr * 16) + hx_st.find(a_st[i])
    return tmpr

finp_st = sys.argv[1]
fout_st = finp_st + ".cas"

if finp_st.lower() == "--help".lower():
    print "bin2cas - 201012221554 - Paulo Silva (GPL licence)"
    print "converts a binary file into a CoCo2 .tap file"
    print "usage: python bin2cas.py yourfile.bin"
    print "the result will be a neighbour file named yourfile.bin.cas"
    print "this converter were made based on information from http://www.cs.unc.edu/~yakowenk/coco/text/tapeformat.html"
    sys.exit()


finp_fl = open(finp_st, "r")
fout_fl = open(fout_st, "w")

lfl = os.path.getsize(finp_st) # lfl=lof(1)

for i in range(0, 128, 1): # - 0x55 byte synchronism, 128 times...
    fout_fl.write(chr(0x55))

fout_fl.write(chr(0x55)) # - two "magic bytes"
fout_fl.write(chr(0x3C))
fout_fl.write(chr(0x00)) # - block type: filename
fout_fl.write(chr(0x0F)) # - data lenght

infnam_st = "ABCDEFGH"
infnam_st = infnam_st + "                "
infnam_st = infnam_st[:8] # - filename - 8 characters
for i in infnam_st:
    fout_fl.write(i)
    # fout_fl.write(infnam_st[i])

fout_fl.write(chr(0x02)) # - machine code
fout_fl.write(chr(0x00)) # - ascii flag: binary
fout_fl.write(chr(0x00)) # - gap flag
fout_fl.write(chr(0x0C)) # - machine code starting address
fout_fl.write(chr(0x00))
fout_fl.write(chr(0x0C)) # - machine code loading address
fout_fl.write(chr(0x00))
fout_fl.write(chr(0x4D)) # - checksum (bitwiseand 255)
fout_fl.write(chr(0x55)) # - "magic byte"

for i in range(0, 128, 1): # - 0x55 byte synchronism, 128 times...
    fout_fl.write(chr(0x55))

while True:
    if lfl < 0:break
    fout_fl.write(chr(0x55)) # - two "magic bytes"
    fout_fl.write(chr(0x3C))
    fout_fl.write(chr(0x01)) # - block type: data
    rlf = 0xFF
    if lfl < rlf:rlf = lfl
    # print rlf
    fout_fl.write(chr(rlf)) # - data lenght
    cfl = 255
    if lfl < 255:cfl = lfl
    cksm = cfl + 1
    for i in range(0, 255, 1):
        byte_st = finp_fl.read(1)
        if len(byte_st) == 0:break
        u = ord(byte_st)
        cksm = (cksm + u) % 256 # - cksm=(cksm+u) mod 256
        fout_fl.write(chr(u)) # - writing byte
    fout_fl.write(chr(cksm)) # - writing checksum
    lfl = lfl - 255

fout_fl.write(chr(0x55)) # - "magic byte"
fout_fl.write(chr(0x55)) # - two "magic bytes"
fout_fl.write(chr(0x3C))
fout_fl.write(chr(0xFF)) # - eof
fout_fl.write(chr(0x00)) # - data lenght
fout_fl.write(chr(0xFF)) # - checksum
fout_fl.write(chr(0x55)) # - "magic byte"

finp_fl.close()
fout_fl.close()