92 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			92 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| subroutine genft8(msg,mygrid,bcontest,msgsent,msgbits,itone)
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| 
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| ! Encode an FT8 message, producing array itone().
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|   
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|   use crc
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|   use packjt
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|   include 'ft8_params.f90'
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|   character*22 msg,msgsent
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|   character*6 mygrid,g1,g2,g3,g4
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|   character*87 cbits
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|   logical*1 bcontest
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|   logical isgrid
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|   integer*4 i4Msg6BitWords(12)                !72-bit message as 6-bit words
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|   integer*1 msgbits(KK),codeword(3*ND)
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|   integer*1, target:: i1Msg8BitBytes(11)
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|   integer itone(NN)
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|   integer icos7(0:6)
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|   data icos7/2,5,6,0,4,1,3/                   !Costas 7x7 tone pattern
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| 
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|   isgrid(g1)=g1(1:1).ge.'A' .and. g1(1:1).le.'R' .and. g1(2:2).ge.'A' .and. &
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|        g1(2:2).le.'R' .and. g1(3:3).ge.'0' .and. g1(3:3).le.'9' .and.       &
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|        g1(4:4).ge.'0' .and. g1(4:4).le.'9' .and. g1(1:4).ne.'RR73'
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| 
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|   if(bcontest) then
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|      i0=index(msg,' R ') + 3                  !Check for ' R ' in message
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|      g1=msg(i0:i0+3)//'  '
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|      if(isgrid(g1)) then                      !Check for ' R grid'
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|         call grid2deg(g1,dlong,dlat)
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|         dlong=dlong+180.0
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|         if(dlong.gt.180.0) dlong=dlong-360.0
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|         dlat=-dlat
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|         call deg2grid(dlong,dlat,g2)          !g2=antipodes grid
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|         msg=msg(1:i0-3)//g2(1:4)              !Send message with g2
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|      endif
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|   endif
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| 
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|   call packmsg(msg,i4Msg6BitWords,itype)      !Pack into 12 6-bit bytes
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|   call unpackmsg(i4Msg6BitWords,msgsent)      !Unpack to get msgsent
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| 
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|   if(bcontest) then
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|      i1=index(msgsent(8:22),' ') + 8
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|      g3=msgsent(i1:i1+3)//'  '
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|      if(isgrid(g3)) then
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|         call azdist(mygrid,g3,0.d0,nAz,nEl,nDmiles,nDkm,nHotAz,nHotABetter)
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|         if(ndkm.gt.10000) then
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|            call grid2deg(g3,dlong,dlat)
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|            dlong=dlong+180.0
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|            if(dlong.gt.180.0) dlong=dlong-360.0
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|            dlat=-dlat
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|            call deg2grid(dlong,dlat,g4)
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|            msgsent=msgsent(1:i1-1)//'R '//g4(1:4)
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|         endif
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|      endif
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|   endif
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| 
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|   i3bit=0                                     !### temporary ###
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|   write(cbits,1000) i4Msg6BitWords,32*i3bit
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| 1000 format(12b6.6,b8.8)
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|   read(cbits,1001) i1Msg8BitBytes(1:10)
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| 1001 format(10b8)
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|   i1Msg8BitBytes(10)=iand(i1Msg8BitBytes(10),128+64+32)
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|   i1Msg8BitBytes(11)=0
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|   icrc12=crc12(c_loc(i1Msg8BitBytes),11)
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| 
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| ! For reference, here's how to check the CRC
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| !  i1Msg8BitBytes(10)=icrc12/256
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| !  i1Msg8BitBytes(11)=iand (icrc12,255)
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| !  checksumok = crc12_check(c_loc (i1Msg8BitBytes), 11)
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| !  if( checksumok ) write(*,*) 'Good checksum'
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| 
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|   write(cbits,1003) i4Msg6BitWords,i3bit,icrc12
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| 1003 format(12b6.6,b3.3,b12.12)
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|   read(cbits,1004) msgbits
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| 1004 format(87i1)
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| 
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|   call encode174(msgbits,codeword)      !Encode the test message
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| 
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| ! Message structure: S7 D29 S7 D29 S7
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|   itone(1:7)=icos7
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|   itone(36+1:36+7)=icos7
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|   itone(NN-6:NN)=icos7
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|   k=7
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|   do j=1,ND
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|      i=3*j -2
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|      k=k+1
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|      if(j.eq.30) k=k+7
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|      itone(k)=codeword(i)*4 + codeword(i+1)*2 + codeword(i+2)
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|   enddo
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| 
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|   return
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| end subroutine genft8
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