HEX2BI.DOC

               Hex2Bin- Compuserve Hex to Binary File Converter



          I originally wrote Hex2Bin so that I could read object files on
     Compuserve at a time when I didn't have any downloading capabilities.
     With a large enough capture buffer you can read CBTerm49.Bin and
     convert it into a useable form with Hex2Bin.
     
          When you read filename.BIN or filename.IMG on compuserve you will
     be looking at something a little like this: 1800000000801....  This
     Hexadecimal form of the file contains headers, and two hex bytes for
     every byte of the file. Therefor your capture buffer will need to be
     about two and a half times bigger than the actual object size of the
     file. You will also take significantly more connect time to read the
     file than you would need if you had Xmodem capabilities.

          The best use of this utility is to get a copy of CBTerm. CBTerm
     has Xmodem uploading and downloading capabilities. Chris Dos supports
     CBTerm version 4.5. CBTerm version 4.9 even allows you to Upload and
     Download over DataPac.
     
          Hex2Bin was written for use with the disk drive. You save the
     file you read into your capture buffer as a sequential file on disc.
     Hex2Bin then asks for the input filename- the name you saved it with,
     and the output filename- the name of the resulting object program you
     want to use. These names MUST be different. Hex2Bin reads and writes
     to the disk almost simultaneously- keeping two cahnnels open at the
     same time.
          Converting files to their object form in this method takes a
     considerable amount of time,but no save is needed when the program is
     done. Because Hex2Bin is very I/O bound compileing the program will
     not speed up the program with any significance, nor will removeing the
     Remarks, most of which never get executed.
          Hex2Bin lets you see the number of characters being written to
     the disk while it is running so that you can see that it is still
     busy.
     
          Hex2Bin.Seq is a textual form of this program. You can convert it
     to true Basic useing Txt2Bas- a short to type in Basic program to
     convert sequential Basic Programs to true Basic. When converting
     Hex2Bin to Basic respond N to the 'Upper Characters?' prompt in
     Txt2Bas. When Txt2Bas is finished the useable version of Hex2Bin will
     be in memory.
          To use Hex2Bin to read CBTerm you buffer will need about 30K of
     space. The terminal package I originally got with my Modem from
     Commodore- Teleterm/64 has sufficient space.
     
          Some Compuserve Binary files converted with this utility may
     appear with an invalid line number at the start. In that case change
     the setting in line 380 from header=0 to header=1 and re-run the
     conversion. This causes the program to strip an extra header checksum
     occasionally passed in the first block of data.
          Hex2Bin.Seq is the textual form of this program. Hex2Bin.Bin is
     the tokenized Basic form.
          Remove the 'Rem' in line 520 once you are confident about
     purgeing the destination file whenever you run this program.
                         Tony Romer