diff --git a/lib/bpdecode128_90.f90 b/lib/bpdecode128_90.f90
index 763b91963..c48ba1fa8 100644
--- a/lib/bpdecode128_90.f90
+++ b/lib/bpdecode128_90.f90
@@ -8,18 +8,18 @@ subroutine bpdecode128_90(llr,apmask,maxiterations,message77,cw,nharderror,iter)
   integer*1 cw(N),apmask(N)
   integer*1 decoded(K)
   integer*1 message77(77)
-  integer Nm(12,M)   
-  integer Mn(4,N) 
-  integer nrw(M),ncw(N)
+  integer Nm(11,M)   
+  integer Mn(3,N) 
+  integer nrw(M)
   integer synd(M)
   real tov(4,N)
-  real toc(12,M)
-  real tanhtoc(12,M)
+  real toc(11,M)
+  real tanhtoc(11,M)
   real zn(N)
   real llr(N)
   real Tmn
 
-  include "ldpc_128_90_b_reordered_parity.f90"
+  include "ldpc_128_90_reordered_parity.f90"
 
   decoded=0
   toc=0
@@ -39,7 +39,7 @@ subroutine bpdecode128_90(llr,apmask,maxiterations,message77,cw,nharderror,iter)
 ! Update bit log likelihood ratios (tov=0 in iteration 0).
     do i=1,N
       if( apmask(i) .ne. 1 ) then
-        zn(i)=llr(i)+sum(tov(1:ncw(i),i))
+        zn(i)=llr(i)+sum(tov(1:ncw,i))
       else
         zn(i)=llr(i)
       endif
@@ -74,7 +74,7 @@ subroutine bpdecode128_90(llr,apmask,maxiterations,message77,cw,nharderror,iter)
         ncnt=ncnt+1
       endif
 !      write(*,*) iter,ncheck,nd,ncnt
-      if( ncnt .ge. 5 .and. iter .ge. 10 .and. ncheck .gt. 15) then
+      if( ncnt .ge. 3 .and. iter .ge. 5 .and. ncheck .gt. 10) then
         nharderror=-1
         return
       endif
@@ -86,7 +86,7 @@ subroutine bpdecode128_90(llr,apmask,maxiterations,message77,cw,nharderror,iter)
       do i=1,nrw(j)
         ibj=Nm(i,j)
         toc(i,j)=zn(ibj)  
-        do kk=1,4 ! subtract off what the bit had received from the check
+        do kk=1,ncw ! subtract off what the bit had received from the check
           if( Mn(kk,ibj) .eq. j ) then  
             toc(i,j)=toc(i,j)-tov(kk,ibj)
           endif
@@ -96,11 +96,11 @@ subroutine bpdecode128_90(llr,apmask,maxiterations,message77,cw,nharderror,iter)
 
 ! send messages from check nodes to variable nodes
     do i=1,M
-      tanhtoc(1:12,i)=tanh(-toc(1:12,i)/2)
+      tanhtoc(1:11,i)=tanh(-toc(1:11,i)/2)
     enddo
 
     do j=1,N
-      do i=1,ncw(j)
+      do i=1,ncw
         ichk=Mn(i,j)  ! Mn(:,j) are the checks that include bit j
         Tmn=product(tanhtoc(1:nrw(ichk),ichk),mask=Nm(1:nrw(ichk),ichk).ne.j)
         call platanh(-Tmn,y)
diff --git a/lib/bpdecode128_90.f90.save b/lib/bpdecode128_90.f90.save
new file mode 100644
index 000000000..69537afbb
--- /dev/null
+++ b/lib/bpdecode128_90.f90.save
@@ -0,0 +1,116 @@
+subroutine bpdecode128_90(llr,apmask,maxiterations,message77,cw,nharderror,iter)
+!
+! A log-domain belief propagation decoder for the (128,90) code.
+!
+  use iso_c_binding, only: c_loc,c_size_t
+  use crc
+  integer, parameter:: N=128, K=90, M=N-K
+  integer*1 cw(N),apmask(N)
+  integer*1 decoded(K)
+  integer*1 message77(77)
+  integer Nm(12,M)   
+  integer Mn(4,N) 
+  integer nrw(M),ncw(N)
+  integer synd(M)
+  real tov(4,N)
+  real toc(12,M)
+  real tanhtoc(12,M)
+  real zn(N)
+  real llr(N)
+  real Tmn
+
+  include "ldpc_128_90_b_reordered_parity.f90"
+
+  decoded=0
+  toc=0
+  tov=0
+  tanhtoc=0
+! initialize messages to checks
+  do j=1,M
+    do i=1,nrw(j)
+      toc(i,j)=llr((Nm(i,j)))
+    enddo
+  enddo
+
+  ncnt=0
+
+  do iter=0,maxiterations
+
+! Update bit log likelihood ratios (tov=0 in iteration 0).
+    do i=1,N
+      if( apmask(i) .ne. 1 ) then
+        zn(i)=llr(i)+sum(tov(1:ncw(i),i))
+      else
+        zn(i)=llr(i)
+      endif
+    enddo
+
+! Check to see if we have a codeword (check before we do any iteration).
+    cw=0
+    where( zn .gt. 0. ) cw=1
+    ncheck=0
+    do i=1,M
+      synd(i)=sum(cw(Nm(1:nrw(i),i)))
+      if( mod(synd(i),2) .ne. 0 ) ncheck=ncheck+1
+!     if( mod(synd(i),2) .ne. 0 ) write(*,*) 'check ',i,' unsatisfied'
+    enddo
+!   write(*,*) 'number of unsatisfied parity checks ',ncheck
+    if( ncheck .eq. 0 ) then ! we have a codeword - reorder the columns and return it
+      decoded=cw(1:K)
+      call chkcrc13a(decoded,nbadcrc)
+      if(nbadcrc.eq.0) then
+        message77=decoded(1:77)
+        nharderror=count( (2*cw-1)*llr .lt. 0.0 )
+        return
+      endif
+    endif
+
+    if( iter.gt.0 ) then  ! this code block implements an early stopping criterion
+!    if( iter.gt.10000 ) then  ! this code block implements an early stopping criterion
+      nd=ncheck-nclast
+      if( nd .lt. 0 ) then ! # of unsatisfied parity checks decreased
+        ncnt=0  ! reset counter
+      else
+        ncnt=ncnt+1
+      endif
+!      write(*,*) iter,ncheck,nd,ncnt
+      if( ncnt .ge. 3 .and. iter .ge. 5 .and. ncheck .gt. 10) then
+        nharderror=-1
+        return
+      endif
+    endif
+    nclast=ncheck
+
+! Send messages from bits to check nodes 
+    do j=1,M
+      do i=1,nrw(j)
+        ibj=Nm(i,j)
+        toc(i,j)=zn(ibj)  
+        do kk=1,4 ! subtract off what the bit had received from the check
+          if( Mn(kk,ibj) .eq. j ) then  
+            toc(i,j)=toc(i,j)-tov(kk,ibj)
+          endif
+        enddo
+      enddo
+    enddo
+
+! send messages from check nodes to variable nodes
+    do i=1,M
+      tanhtoc(1:12,i)=tanh(-toc(1:12,i)/2)
+    enddo
+
+    do j=1,N
+      do i=1,ncw(j)
+        ichk=Mn(i,j)  ! Mn(:,j) are the checks that include bit j
+        Tmn=product(tanhtoc(1:nrw(ichk),ichk),mask=Nm(1:nrw(ichk),ichk).ne.j)
+        call platanh(-Tmn,y)
+!        y=atanh(-Tmn)
+        tov(i,j)=2*y
+      enddo
+    enddo
+
+  enddo
+  nharderror=-1
+  return
+
+end subroutine bpdecode128_90
diff --git a/lib/encode_128_90.f90 b/lib/encode_128_90.f90
new file mode 100644
index 000000000..e59cf11b6
--- /dev/null
+++ b/lib/encode_128_90.f90
@@ -0,0 +1,58 @@
+subroutine encode_128_90(message77,codeword)
+!
+! Add a 13-bit CRC to a 77-bit message and return a 128-bit codeword
+!
+use, intrinsic :: iso_c_binding
+use iso_c_binding, only: c_loc,c_size_t
+use crc
+
+integer, parameter:: N=128, K=90, M=N-K
+character*90 tmpchar
+integer*1 codeword(N)
+integer*1 gen(M,K)
+integer*1 message77(77),message(K)
+integer*1 pchecks(M)
+integer*1, target :: i1MsgBytes(12)
+include "ldpc_128_90_generator.f90"
+logical first
+data first/.true./
+save first,gen
+
+if( first ) then ! fill the generator matrix
+  gen=0
+  do i=1,M
+    do j=1,23
+      read(g(i)(j:j),"(Z1)") istr
+        ibmax=4
+        if(j.eq.23) ibmax=2 
+        do jj=1, ibmax 
+          icol=(j-1)*4+jj
+          if( btest(istr,4-jj) ) gen(i,icol)=1
+        enddo
+    enddo
+  enddo
+first=.false.
+endif
+
+! Add 13 bit CRC to form 90-bit message+CRC13
+write(tmpchar,'(77i1)') message77
+tmpchar(78:80)='000'
+i1MsgBytes=0
+read(tmpchar,'(10b8)') i1MsgBytes(1:10)
+ncrc13 = crc13 (c_loc (i1MsgBytes), 12)
+write(tmpchar(78:90),'(b13)') ncrc13
+read(tmpchar,'(90i1)') message
+
+do i=1,M
+  nsum=0
+  do j=1,K 
+    nsum=nsum+message(j)*gen(i,j)
+  enddo
+  pchecks(i)=mod(nsum,2)
+enddo
+
+codeword(1:K)=message
+codeword(K+1:N)=pchecks
+
+return
+end subroutine encode_128_90
diff --git a/lib/genmsk_128_90.f90 b/lib/genmsk_128_90.f90
new file mode 100644
index 000000000..8e6e4ba20
--- /dev/null
+++ b/lib/genmsk_128_90.f90
@@ -0,0 +1,114 @@
+subroutine genmsk_128_90(msg0,mygrid,ichk,bcontest,msgsent,i4tone,itype)
+! s8 + 48bits + s8 + 80 bits = 144 bits (72ms message duration)
+!
+! Encode an MSK144 message
+! Input:
+!   - msg0     requested message to be transmitted
+!   - ichk     if ichk=1, return only msgsent
+!              if ichk.ge.10000, set imsg=ichk-10000 for short msg
+!   - msgsent  message as it will be decoded
+!   - i4tone   array of audio tone values, 0 or 1
+!   - itype    message type 
+!                 1 = standard message  "Call_1 Call_2 Grid/Rpt"
+!                 2 = type 1 prefix
+!                 3 = type 1 suffix
+!                 4 = type 2 prefix
+!                 5 = type 2 suffix
+!                 6 = free text (up to 13 characters)
+!                 7 = short message     "<Call_1 Call2> Rpt"
+
+  use iso_c_binding, only: c_loc,c_size_t
+  use packjt77
+  character*37 msg0
+  character*37 message                    !Message to be generated
+  character*37 msgsent                    !Message as it will be received
+  character*77 c77
+  character*6 mygrid
+  integer*4 i4tone(144)
+  integer*1 codeword(128)
+  integer*1 msgbits(77) 
+  integer*1 bitseq(144)                   !Tone #s, data and sync (values 0-1)
+  integer*1 s8(8)
+  logical bcontest
+  real*8 pp(12)
+  real*8 xi(864),xq(864),pi,twopi
+  data s8/0,1,1,1,0,0,1,0/
+  equivalence (ihash,i1hash)
+  logical first
+  data first/.true./
+  save
+
+  if(first) then
+    first=.false.
+    nsym=128
+    pi=4.0*atan(1.0)
+    twopi=8.*atan(1.0)
+    do i=1,12
+      pp(i)=sin((i-1)*pi/12)
+    enddo
+  endif
+
+  if(msg0(1:1).eq.'@') then                    !Generate a fixed tone
+     read(msg0(2:5),*,end=1,err=1) nfreq       !at specified frequency
+     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
+
+     if(message(1:1).eq.'<') then
+        call genmsk40(message,msgsent,ichk,i4tone,itype)
+        if(itype.lt.0) go to 999
+        i4tone(41)=-40
+        go to 999
+     endif
+
+     call pack77(message,i3,n3,c77) 
+     call unpack77(c77,msgsent) !Unpack to get msgsent
+     if(ichk.eq.1) go to 999
+     read(c77,"77i1") msgbits
+     call encode_128_90(msgbits,codeword)
+
+!Create 144-bit channel vector:
+!8-bit sync word + 48 bits + 8-bit sync word + 80 bits
+     bitseq=0 
+     bitseq(1:8)=s8
+     bitseq(9:56)=codeword(1:48)
+     bitseq(57:64)=s8
+     bitseq(65:144)=codeword(49:128)
+     bitseq=2*bitseq-1
+
+     xq(1:6)=bitseq(1)*pp(7:12)   !first bit is mapped to 1st half-symbol on q
+     do i=1,71
+       is=(i-1)*12+7
+       xq(is:is+11)=bitseq(2*i+1)*pp
+     enddo 
+     xq(864-5:864)=bitseq(1)*pp(1:6)   !last half symbol
+     do i=1,72                                    
+       is=(i-1)*12+1
+       xi(is:is+11)=bitseq(2*i)*pp
+     enddo
+! Map I and Q  to tones. 
+    i4tone=0 
+    do i=1,72
+      i4tone(2*i-1)=(bitseq(2*i)*bitseq(2*i-1)+1)/2;
+      i4tone(2*i)=-(bitseq(2*i)*bitseq(mod(2*i,144)+1)-1)/2;
+    enddo
+  endif
+
+! Flip polarity
+  i4tone=-i4tone+1
+
+999 return
+end subroutine genmsk_128_90
diff --git a/lib/ldpcsim128_90.f90 b/lib/ldpcsim128_90.f90
index 6ddfda22d..ebe759806 100644
--- a/lib/ldpcsim128_90.f90
+++ b/lib/ldpcsim128_90.f90
@@ -1,132 +1,134 @@
-program ldpcsim
+program ldpcsim128_90
 
-use packjt
-integer, parameter:: NRECENT=10, N=128, K=90, M=N-K
-character*12 recent_calls(NRECENT)
-character*22 msg,msgsent,msgreceived
-character*96 tmpchar
-character*8 arg
-integer*1 codeword(N), message77(77)
-integer*1 apmask(N),cw(N)
-integer*1 msgbits(77)
-integer*4 i4Msg6BitWords(13)
-integer nerrtot(0:N),nerrdec(0:N)
-real*8 rxdata(N), rxavgd(N)
-real llr(N)
+! Simulate the performance of the (128,90) code that is used in
+! the second incarnation of MSK144.
 
-do i=1,NRECENT
-  recent_calls(i)='            '
-enddo
-nerrtot=0
-nerrdec=0
+  use packjt77
+  integer, parameter:: NRECENT=10, N=128, K=90, M=N-K
+  character*12 recent_calls(NRECENT)
+  character*37 msg,msgsent,msgreceived
+  character*77 c77 
+  character*8 arg
+  integer*1 codeword(N), message77(77)
+  integer*1 apmask(N),cw(N)
+  integer*1 msgbits(77)
+  integer*4 i4Msg6BitWords(13)
+  integer nerrtot(0:N),nerrdec(0:N)
+  real*8 rxdata(N), rxavgd(N)
+  real llr(N)
 
-nargs=iargc()
-if(nargs.ne.4) then
-   print*,'Usage: ldpcsim  niter   navg  #trials  s '
-   print*,'eg:    ldpcsim    10     1     1000    0.75'
-   return
-endif
-call getarg(1,arg)
-read(arg,*) max_iterations 
-call getarg(2,arg)
-read(arg,*) navg 
-call getarg(3,arg)
-read(arg,*) ntrials 
-call getarg(4,arg)
-read(arg,*) s
+  do i=1,NRECENT
+    recent_calls(i)='            '
+  enddo
+  nerrtot=0
+  nerrdec=0
 
-rate=real(K)/real(N)
+  nargs=iargc()
+  if(nargs.ne.4) then
+    print*,'Usage: ldpcsim  niter   navg  #trials  s '
+    print*,'eg:    ldpcsim    10     1     1000    0.75'
+    return
+  endif
+  call getarg(1,arg)
+  read(arg,*) max_iterations 
+  call getarg(2,arg)
+  read(arg,*) navg 
+  call getarg(3,arg)
+  read(arg,*) ntrials 
+  call getarg(4,arg)
+  read(arg,*) s
 
-write(*,*) "rate: ",rate
-write(*,*) "niter= ",max_iterations," navg= ",navg," s= ",s
+  rate=real(77)/real(N)
+
+  write(*,*) "rate: ",rate
+  write(*,*) "niter= ",max_iterations," navg= ",navg," s= ",s
+
+  msg="K1ABC RR73; W9XYZ <KH1/KH7Z> -12"
+  i3=0
+  n3=1
+  call pack77(msg,i3,n3,c77)
+  call unpack77(c77,msgsent)
+  read(c77,'(77i1)') msgbits
 
-!msg="K9AN K1JT EN50"
-msg="G4WJS K1JT FN20"
-  call packmsg(msg,i4Msg6BitWords,itype,.false.) !Pack into 12 6-bit bytes
-  call unpackmsg(i4Msg6BitWords,msgsent,.false.,'      ') !Unpack to get msgsent
   write(*,*) "message sent ",msgsent
 
-  tmpchar=' '
-  write(tmpchar,'(12b6.6)') i4Msg6BitWords(1:12)
-  tmpchar(73:77)="00000"   !i5bit
-  read(tmpchar,'(77i1)') msgbits(1:77)
-
   write(*,*) 'msgbits'
-  write(*,'(28i1,1x,28i1,1x,16i1,1x,5i1)') msgbits
+  write(*,'(77i1)') msgbits
 
 ! msgbits is the 77-bit message, codeword is 128 bits
-  call encode128_90(msgbits,codeword)
+  call encode_128_90(msgbits,codeword)
 
-  call init_random_seed()
+!  call init_random_seed()
 
-write(*,*) "Eb/N0  SNR2500   ngood  nundetected  sigma    psymerr"
-do idb = 14,-6,-1 
-  db=idb/2.0-1.0
-  sigma=1/sqrt( 2*rate*(10**(db/10.0)) )
-  ngood=0
-  nue=0
-  nbadcrc=0
-  nsumerr=0
+  write(*,*) "Eb/N0  SNR2500   ngood  nundetected  sigma    psymerr"
+  do idb = 14,0,-1 
+    db=idb/2.0-1.0
+    sigma=1/sqrt( 2*rate*(10**(db/10.0)) )
+    ngood=0
+    nue=0
+    nbadcrc=0
+    nsumerr=0
 
-  do itrial=1, ntrials
-    rxavgd=0d0
-    do iav=1,navg
-      call sgran()
+    do itrial=1, ntrials
+      rxavgd=0d0
+      do iav=1,navg
+!        call sgran()
 ! Create a realization of a noisy received word
-      do i=1,N
-        rxdata(i) = 2.0*codeword(i)-1.0 + sigma*gran()
+        do i=1,N
+          rxdata(i) = 2.0*codeword(i)-1.0 + sigma*gran()
+        enddo
+        rxavgd=rxavgd+rxdata
       enddo
-      rxavgd=rxavgd+rxdata
-    enddo
-    rxdata=rxavgd
-    nerr=0
-    do i=1,N
-      if( rxdata(i)*(2*codeword(i)-1.0) .lt. 0 ) nerr=nerr+1
-    enddo
-    nerrtot(nerr)=nerrtot(nerr)+1
+      rxdata=rxavgd
+      nerr=0
+      do i=1,N
+        if( rxdata(i)*(2*codeword(i)-1.0) .lt. 0 ) nerr=nerr+1
+      enddo
+      nerrtot(nerr)=nerrtot(nerr)+1
 
-    rxav=sum(rxdata)/N
-    rx2av=sum(rxdata*rxdata)/N
-    rxsig=sqrt(rx2av-rxav*rxav)
-    rxdata=rxdata/rxsig
+      rxav=sum(rxdata)/N
+      rx2av=sum(rxdata*rxdata)/N
+      rxsig=sqrt(rx2av-rxav*rxav)
+      rxdata=rxdata/rxsig
 ! The s parameter can be tuned to trade a few tenth's dB of threshold for an order of
 ! magnitude in UER 
-    if( s .lt. 0 ) then
-      ss=sigma
-    else 
-      ss=s
-    endif
+      if( s .lt. 0 ) then
+        ss=sigma
+      else 
+        ss=s
+      endif
 
-    llr=2.0*rxdata/(ss*ss)
+      llr=2.0*rxdata/(ss*ss)
 
-    apmask=0
+      apmask=0
 ! max_iterations is max number of belief propagation iterations
-    call bpdecode128_90(llr, apmask, max_iterations, message77, cw, nharderrors, niterations)
+      call bpdecode128_90(llr, apmask, max_iterations, message77, cw, nharderrors, niterations)
 
 ! If the decoder finds a valid codeword, nharderrors will be .ge. 0.
-    if( nharderrors .ge. 0 ) then
-       call extractmessage77(message77,msgreceived)
-       nhw=count(cw.ne.codeword)
-       if(nhw.eq.0) then ! this is a good decode
+      if( nharderrors .ge. 0 ) then
+        write(c77,'(77i1)') message77
+        call unpack77(c77,msgreceived)
+        nhw=count(cw.ne.codeword)
+        if(nhw.eq.0) then ! this is a good decode
           ngood=ngood+1
           nerrdec(nerr)=nerrdec(nerr)+1 
-       else              ! this is an undetected error
+        else              ! this is an undetected error
           nue=nue+1
-       endif
-    endif
-    nsumerr=nsumerr+nerr
+        endif
+      endif
+      nsumerr=nsumerr+nerr
+    enddo
+
+    snr2500=db+10*log10(rate*2000.0/2500.0) ! symbol rate is 2000 s^-1 and ref BW is 2500 Hz.
+    pberr=real(nsumerr)/real(ntrials*N)
+    write(*,"(f4.1,4x,f5.1,1x,i8,1x,i8,7x,f5.2,3x,e10.3)") db,snr2500,ngood,nue,ss,pberr
+  
   enddo
 
-  snr2500=db-2.5
-  pberr=real(nsumerr)/real(ntrials*N)
-  write(*,"(f4.1,4x,f5.1,1x,i8,1x,i8,7x,f5.2,3x,e10.3)") db,snr2500,ngood,nue,ss,pberr
-  
-enddo
+  open(unit=23,file='nerrhisto.dat',status='unknown')
+  do i=0,N
+    write(23,'(i4,2x,i10,i10,f10.2)') i,nerrdec(i),nerrtot(i),real(nerrdec(i))/real(nerrtot(i)+1e-10)
+  enddo
+  close(23)
 
-open(unit=23,file='nerrhisto.dat',status='unknown')
-do i=0,N
-  write(23,'(i4,2x,i10,i10,f10.2)') i,nerrdec(i),nerrtot(i),real(nerrdec(i))/real(nerrtot(i)+1e-10)
-enddo
-close(23)
-
-end program ldpcsim
+end program ldpcsim128_90
diff --git a/lib/ldpcsim144.f90 b/lib/ldpcsim144.f90
index 31271d5a9..20ce88c18 100644
--- a/lib/ldpcsim144.f90
+++ b/lib/ldpcsim144.f90
@@ -41,7 +41,7 @@ call getarg(4,arg)
 read(arg,*) s
 
 ! don't count hash bits as data bits
-K=80
+K=72
 N=128
 rate=real(K)/real(N)
 
@@ -161,7 +161,7 @@ do idb = 14,-6,-1
       endif
     endif
   enddo
-  snr2500=db-3.0
+  snr2500=db-3.5
   write(*,"(f4.1,4x,f5.1,1x,i8,1x,i8,1x,i8,8x,f5.2)") db,snr2500,ngood,nue,nbadhash,ss
 
 enddo