subroutine gen9(msg0,ichk,msgsent,i4tone,itype) ! Encodes a JT9 message and returns msgsent, the message as it will ! be decoded, and an integer array i4tone(85) of 9-FSK tone values ! in the range 0-8. use packjt character*22 msg0 character*22 message !Message to be generated character*22 msgsent !Message as it will be received integer*4 i4Msg6BitWords(13) !72-bit message as 6-bit words integer*1 i1Msg8BitBytes(13) !72 bits and zero tail as 8-bit bytes integer*1 i1EncodedBits(207) !Encoded information-carrying bits integer*1 i1ScrambledBits(207) !Encoded bits after interleaving integer*4 i4DataSymbols(69) !Data symbols (values 0-7) integer*4 i4GrayCodedSymbols(69) !Gray-coded symbols (values 0-7) integer*4 i4tone(85) !Tone #s, data and sync (values 0-8) include 'jt9sync.f90' save if(msg0(1:1).eq.'@') then read(msg0(2:5),*,end=1,err=1) nfreq go to 2 1 nfreq=1000 2 i4tone(1)=nfreq else message=msg0 do i=1,22 if(ichar(message(i:i)).eq.0) then message(i:)=' ' exit endif enddo do i=1,22 !Strip leading blanks if(message(1:1).ne.' ') exit message=message(i+1:) enddo call packmsg(message,i4Msg6BitWords,itype) !Pack into 12 6-bit bytes call unpackmsg(i4Msg6BitWords,msgsent,' ') !Unpack to get msgsent if(ichk.ne.0) go to 999 call entail(i4Msg6BitWords,i1Msg8BitBytes) !Add tail, make 8-bit bytes nsym2=206 call encode232(i1Msg8BitBytes,nsym2,i1EncodedBits) !Encode K=32, r=1/2 i1EncodedBits(207)=0 call interleave9(i1EncodedBits,1,i1ScrambledBits) !Interleave bits i1ScrambledBits(207)=0 call packbits(i1ScrambledBits,69,3,i4DataSymbols) !Pk 3-bits into words call graycode(i4DataSymbols,69,1,i4GrayCodedSymbols) !Apply Gray code ! Insert sync symbols at ntone=0 and add 1 to the data-tone numbers. j=0 do i=1,85 if(isync(i).eq.1) then i4tone(i)=0 else j=j+1 i4tone(i)=i4GrayCodedSymbols(j)+1 endif enddo endif 999 return end subroutine gen9