bin2cas.py

#!/usr/bin/python
# -*- coding: latin-1 -*-
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"
else:
  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()