to8xx

#!/data/data/com.termux/files/usr/bin/python

import sys

global chksum
chksum = 0

def chkwrite(outfile, bytearray):
    global chksum
    outfile.write(bytearray)
    for byte in bytearray:
        chksum += int(byte)

def main(argv):

    if len(argv) !=2:
        print("Wrong Syntax!\nUsage: %s filename\n" %argv[0])
        sys.exit(10)

    infile = open(argv[1] + '.bin', 'rb')
    outfile = open(argv[1] + '.83p', 'wb')

    data = infile.read()

    tmp=len(data)+2+2+13
    outfile.write(b'**TI83**')
    outfile.write(b'\x1a\x0a\x00')
    outfile.write(b'File generated by to8xx in python'.ljust(42, b' '))
    outfile.write(tmp.to_bytes(2, 'little'))

    chkwrite(outfile, b'\x0b\x00')

    tmp = len(data) + 2;
    chkwrite(outfile, tmp.to_bytes(2, 'little'))
    chkwrite(outfile, b'\x06')

    chkwrite(outfile, argv[1].upper().encode().ljust(8, b'\x00'))

    tmp = len(data) + 2
    chkwrite(outfile, tmp.to_bytes(2, 'little'))
    chkwrite(outfile, len(data).to_bytes(2, 'little'))

    chkwrite(outfile, data)

    print("wrote almost all..%d\n" %chksum)

    chkwrite(outfile, (chksum&65535).to_bytes(2, 'little'))

    infile.close()
    outfile.close()

    print("wrote all!!\n")

if __name__ == '__main__':
    main(sys.argv)