>Can anybody explain step by step how to open,read,convert a file (hex format) into readable format (ascii), or may be give some concept how to do it.

Hi, Andreas

Does your hex file come in a normalized known format or is it just a series of hex codes (such as 32303031313131340D0A?)

If it is just a series of hex codes, you could do something of the kind
<NotRobust>

lnIn = fopen(lcHexFile)
lnOut = fcreate(lcAsciiFile)
do while !feof(lnIn)
  lcHex = fread(lnIn,2)
  lcAscii = chr(val("0x"+lcHex))
  fwrite(lnOut,lcAscii)
enddo
fclose(lnIn)
fclose(lnOut)

</NotRobust>

bye