Fix munging on 671x boards

diff --git a/comedi/drivers/ni_mio_common.c b/comedi/drivers/ni_mio_common.c
index 77c93a7db1915dd8bbd608884ee3b00d3efc2bed..32c55c9a236ed079e57a35ed407619a9473ebef9 100644 (file)
--- a/comedi/drivers/ni_mio_common.c
+++ b/comedi/drivers/ni_mio_common.c
@@ -1855,11 +1855,14 @@ static int ni_ao_insn_write_671x(comedi_device *dev,comedi_subdevice *s,
        comedi_insn *insn,lsampl_t *data)
 {
        unsigned int chan = CR_CHAN(insn->chanspec);
+       lsampl_t d;
 
        ni_ao_config_chanlist(dev,s,&insn->chanspec,1);
 
-       devpriv->ao[chan] = data[insn->n-1];
-       ao_win_out(data[insn->n-1],DACx_Direct_Data_671x(chan));
+       d = data[insn->n-1];
+       devpriv->ao[chan] = d;
+       d -= 1 << (boardtype.aobits - 1);
+       ao_win_out(d,DACx_Direct_Data_671x(chan));
 
        return insn->n;
 }