WSJT-X/lib/genmsk40.f90

67 lines
1.6 KiB
Fortran

subroutine genmsk40(msg,msgsent,ichk,itone,itype)
use hashing
character*37 msg,msgsent,hashmsg
character*4 crpt,rpt(0:15)
logical first
integer*4 itone(144)
integer*1 message(16),codeword(32),bitseq(40)
integer*1 s8r(8)
data s8r/1,0,1,1,0,0,0,1/ ! Sync word is reversed wrt msk144 sync word.
data first/.true./
data rpt/"-03 ","+00 ","+03 ","+06 ","+10 ","+13 ","+16 ", &
"R-03","R+00","R+03","R+06","R+10","R+13","R+16", &
"RRR ","73 "/
save first,rpt
itype=-1
msgsent='*** bad message ***'
itone=0
i1=index(msg,'>')
if(i1.lt.9) go to 900
call fmtmsg(msg,iz)
crpt=msg(i1+2:i1+5)
do i=0,15
if(crpt.eq.rpt(i)) go to 10
enddo
go to 900
10 irpt=i !Report index, 0-15
if(ichk.lt.10000) then
hashmsg=msg(2:i1-1)
call hash(hashmsg,37,ihash)
ihash=iand(ihash,4095) !12-bit hash
ig=16*ihash + irpt !4-bit report
else
ig=ichk-10000
endif
do i=1,16
message(i)=iand(1,ishft(ig,1-i))
enddo
call encode_msk40(message,codeword)
! write(*,'(a6,i6,2x,a6,i6,2x,a6,i6)') ' msg: ',ig,'rprt: ',irpt,'hash: ',ihash
! write(*,'(a6,32i1)') ' cw: ',codeword
bitseq(1:8)=s8r
bitseq(9:40)=codeword
bitseq=2*bitseq-1
! Map I and Q to tones.
itone=0
do i=1, 20
itone(2*i-1)=(bitseq(2*i)*bitseq(2*i-1)+1)/2;
itone(2*i)=-(bitseq(2*i)*bitseq(mod(2*i,40)+1)-1)/2;
enddo
! Flip polarity
itone=-itone+1
msgsent=msg
itype=7
900 return
end subroutine genmsk40