WSJT-X/lib/fsk4hf/genft8.f90
Joe Taylor db9181d1cd Tidy up some details for 72-bit contest mode in FT8.
git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@7974 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
2017-08-01 18:16:01 +00:00

92 lines
2.8 KiB
Fortran

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