Experimenting with full packing of 72-bit messages using an intermediate base64 alphabet (12 x 6-bit characters)

lib/ft8/extractmessage174.f90

@@ -2,13 +2,15 @@ subroutine extractmessage174(decoded,msgreceived,ncrcflag)
   use iso_c_binding, only: c_loc,c_size_t
   use crc
   use packjt
-
+  character*68 alphabet
   character*22 msgreceived
   character*87 cbits
   integer*1 decoded(87)
   integer*1, target::  i1Dec8BitBytes(11)
   integer*4 i4Dec6BitWords(12)
 
+  alphabet='0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ-+/?. abcdefghijklmnopqrstuvwxyz'
+
 ! Write decoded bits into cbits: 75-bit message plus 12-bit CRC
   write(cbits,1000) decoded
 1000 format(87i1)
@@ -31,7 +33,15 @@ subroutine extractmessage174(decoded,msgreceived,ncrcflag)
       enddo
       i4Dec6BitWords(ibyte)=itmp
     enddo
-    call unpackmsg(i4Dec6BitWords,msgreceived,.false.,'      ')
+
+    !call unpackmsg(i4Dec6BitWords,msgreceived,.false.,'      ')
+
+    msgreceived='                      '
+    do ibyte=1,12
+      itmp=i4Dec6BitWords(ibyte)
+      msgreceived(ibyte:ibyte) = alphabet(itmp+1:itmp+1)
+    enddo
+    
     ncrcflag=1
   else
     msgreceived=' '

lib/ft8/ft8b.f90

@@ -7,7 +7,7 @@ subroutine ft8b(dd0,newdat,nQSOProgress,nfqso,nftx,ndepth,lapon,lapcqonly,   &
   include 'ft8_params.f90'
   parameter(NP2=2812)
   character*37 msg37
-  character message*22,msgsent*22
+  character message*22,msgsent*22,origmsg*22
   character*12 mycall12,hiscall12
   character*6 mycall6,mygrid6,hiscall6,c1,c2
   character*87 cbits
@@ -378,7 +378,7 @@ subroutine ft8b(dd0,newdat,nQSOProgress,nfqso,nftx,ndepth,lapon,lapcqonly,   &
      if(nbadcrc.eq.0) then
         decoded0=decoded
         if(i3bit.eq.1) decoded(57:)=0
-        call extractmessage174(decoded,message,ncrcflag)
+        call extractmessage174(decoded,origmsg,ncrcflag)
         decoded=decoded0
 
 ! This needs fixing for messages with i3bit=1:        
@@ -399,40 +399,42 @@ subroutine ft8b(dd0,newdat,nQSOProgress,nfqso,nftx,ndepth,lapon,lapcqonly,   &
         if(xsnr .lt. -24.0) xsnr=-24.0
         
         
-        if(i3bit.eq.1) then
+!        if(i3bit.eq.1) then
-           do i=1,12
+!           do i=1,12
-              i1hiscall(i)=ichar(hiscall12(i:i))
+!              i1hiscall(i)=ichar(hiscall12(i:i))
-           enddo
+!           enddo
-           icrc10=crc10(c_loc(i1hiscall),12)
+!           icrc10=crc10(c_loc(i1hiscall),12)
-           write(cbits,1001) decoded
+!           write(cbits,1001) decoded
-1001       format(87i1)
+!1001       format(87i1)
-           read(cbits,1002) ncrc10,nrpt
+!           read(cbits,1002) ncrc10,nrpt
-1002       format(56x,b10,b6)
+!1002       format(56x,b10,b6)
-           irpt=nrpt-30
+!           irpt=nrpt-30
-           i1=index(message,' ')
+!           i1=index(message,' ')
-           i2=index(message(i1+1:),' ') + i1
+!           i2=index(message(i1+1:),' ') + i1
-           c1=message(1:i1)//'   '
+!           c1=message(1:i1)//'   '
-           c2=message(i1+1:i2)//'   '
+!           c2=message(i1+1:i2)//'   '
+!
+!           if(ncrc10.eq.icrc10) msg37=c1//' RR73; '//c2//' <'//      &
+!                trim(hiscall12)//'>    '
+!           if(ncrc10.ne.icrc10) msg37=c1//' RR73; '//c2//' <...>    '
+!           
+!!           msg37=c1//' RR73; '//c2//' <...>    '
+!           write(msg37(35:37),1010) irpt
+!1010       format(i3.2)
+!           if(msg37(35:35).ne.'-') msg37(35:35)='+'
+!           
+!           iz=len(trim(msg37))
+!           do iter=1,10                           !Collapse multiple blanks
+!              ib2=index(msg37(1:iz),'  ')
+!              if(ib2.lt.1) exit
+!              msg37=msg37(1:ib2)//msg37(ib2+2:)
+!              iz=iz-1
+!           enddo
+!        else
+!           msg37=message//'               '
+!        endif
 
-           if(ncrc10.eq.icrc10) msg37=c1//' RR73; '//c2//' <'//      &
+        msg37=origmsg//'               '
-                trim(hiscall12)//'>    '
-           if(ncrc10.ne.icrc10) msg37=c1//' RR73; '//c2//' <...>    '
-           
-!           msg37=c1//' RR73; '//c2//' <...>    '
-           write(msg37(35:37),1010) irpt
-1010       format(i3.2)
-           if(msg37(35:35).ne.'-') msg37(35:35)='+'
-           
-           iz=len(trim(msg37))
-           do iter=1,10                           !Collapse multiple blanks
-              ib2=index(msg37(1:iz),'  ')
-              if(ib2.lt.1) exit
-              msg37=msg37(1:ib2)//msg37(ib2+2:)
-              iz=iz-1
-           enddo
-        else
-           msg37=message//'               '
-        endif
 
         if(i3bit.gt.1) then
             msg37(22:22) = char(48 + i3bit)

lib/ft8/genft8.f90

@@ -5,6 +5,7 @@ subroutine genft8(msg,mygrid,bcontest,i3bit,msgsent,msgbits,itone)
   use crc
   use packjt
   include 'ft8_params.f90'
+  character*68 alphabet
   character*22 msg,msgsent
   character*6 mygrid
   character*87 cbits
@@ -16,8 +17,30 @@ subroutine genft8(msg,mygrid,bcontest,i3bit,msgsent,msgbits,itone)
   integer icos7(0:6)
   data icos7/2,5,6,0,4,1,3/                   !Costas 7x7 tone pattern
 
-  call packmsg(msg,i4Msg6BitWords,itype,bcontest) !Pack into 12 6-bit bytes
+  alphabet='0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ-+/?. abcdefghijklmnopqrstuvwxyz'
-  call unpackmsg(i4Msg6BitWords,msgsent,bcontest,mygrid) !Unpack to get msgsent
+
+  itype=6
+  do i=1,12
+    v=index(alphabet, msg(i:i)) - 1
+    i4Msg6BitWords(i)=v
+  enddo
+  !i4Msg6BitWords( 1)=index(alphabet, msg( 1: 2))
+  !i4Msg6BitWords( 2)=index(alphabet, msg( 2: 3))
+  !i4Msg6BitWords( 3)=index(alphabet, msg( 3: 4))
+  !i4Msg6BitWords( 4)=index(alphabet, msg( 4: 5))
+  !i4Msg6BitWords( 5)=index(alphabet, msg( 5: 6))
+  !i4Msg6BitWords( 6)=index(alphabet, msg( 6: 7))
+  !i4Msg6BitWords( 7)=index(alphabet, msg( 7: 8))
+  !i4Msg6BitWords( 8)=index(alphabet, msg( 8: 9))
+  !i4Msg6BitWords( 9)=index(alphabet, msg( 9:10))
+  !i4Msg6BitWords(10)=index(alphabet, msg(10:11))
+  !i4Msg6BitWords(11)=index(alphabet, msg(11:12))
+  !i4Msg6BitWords(12)=index(alphabet, msg(12:13))
+  msgsent='                      '
+  msgsent(1:12)=msg(1:12)
+
+  ! call packmsg(msg,i4Msg6BitWords,itype,bcontest) !Pack into 12 6-bit bytes
+  ! call unpackmsg(i4Msg6BitWords,msgsent,bcontest,mygrid) !Unpack to get msgsent
 
   write(cbits,1000) i4Msg6BitWords,32*i3bit
 1000 format(12b6.6,b8.8)