dvblast startup script with tuning parameters

#!/bin/bash

ADAPTER=$1
if [ ! -f /etc/dvblast/adapter$ADAPTER.cfg ]; then
    echo "No configuration for adapter "$ADAPTER" found."
    exit 1
fi

# read tuning parameters
read -r TRANSPONDERDATA < /etc/dvblast/adapter$ADAPTER.cfg

if [[ ! $TRANSPONDERDATA =~ ^\#TRANSPONDER ]]; then
    echo "No tuning parameters in configuration file of adapter "$ADAPTER"."
    exit 1
fi

# expand tuning parameters into variables
set $TRANSPONDERDATA
SYSTYPE=$2
FREQ=$3
SRATE=$5
POLARITY=$4
FEC=$6
MODULATION=$8
DISEQC=$9

# convert polarity (H/V) to voltage
if [ "$POLARITY" = "V" ]; then
    VOLTAGE="13"
elif [ "$POLARITY" = "H" ]; then
    VOLTAGE="18"
fi

# remove / from FEC
FEC=${FEC/\//}

if [ "$SYSTYPE" = "S1" ]; then
    S2MODULATION=""
elif [ "$SYSTYPE" = "S2" ]; then
    if [ "$MODULATION" = "QPSK" ]; then
        S2MODULATION="-m qpsk"
    elif [ "$MODULATION" = "8PSK" ]; then
        S2MODULATION="-m psk_8"
    else
        echo "Unknown modulation type "$MODULATION"."
        exit 1
    fi
else
    echo "Unknown system type "$SYSTYPE"."
    exit 1
fi

case "$DISEQC" in
    "AA") DISEQCCMD="-S 1"
          ;;
    "AB") DISEQCCMD="-S 2"
          ;;
    "BA") DISEQCCMD="-S 3"
          ;;
    "BB") DISEQCCMD="-S 4"
          ;;
       *) DISEQCCMD=""
          ;;
esac

dvblast --logger --logger-ident 'DVBLAST_ADAPTER'$ADAPTER \
-a $ADAPTER -r /tmp/dvblast.card$ADAPTER -c /etc/dvblast/adapter$ADAPTER.cfg \
-f $FREQ -s $SRATE -v $VOLTAGE -F $FEC $S2MODULATION $DISEQCCMD \
-C -Y -q 1> /dev/null &