hex2dec_octave

#!/bin/bash

#Convert data from Altera hex-file to decimal

function use_help() {
    echo -e "Format isn't correct!
        \rUse \033[1mhex2dec_vram VRAM.hex conv 0 0 12\033[0m to convert format to x0_0 file.
        \rUse \033[1mhex2dec_vram VRAM.hex fft 0 0 12\033[0m to convert format and open data and FFT in Octave session.
        \r\$3 - 32-bit signal select 0 to 7
        \r\$4 - 16 bit sel from 32-bit signal
        \r\$5 - real bit-width of signal"
    exit
}

if [ "$#" -lt 5 ]
then
    use_help
fi

tmp_file="/tmp/vr"

function data_file_prepare() {
    #$1 - data filename
    #$2 - 32-bit signal 0 to 7
    #$3 - 16 bit sel from 32-bit signal
    #$4 - real bit-width of signal
    local hex_bits="$4"
    local max_bits=`echo "2^$hex_bits" | bc`
    local thr_bits=`echo "$max_bits/2-1" | bc`

    if [ "$3" = 0 ]
    then
        local bits_sel="10,11,12,13"
    else
        local bits_sel="6,7,8,9"
    fi

    cut $1 -c$bits_sel | head -n -1 > $tmp_file

    local full_length=`wc -l $tmp_file | cut -d " " -f1`

    octave -q --eval "x = hex2dec(textread(\"$tmp_file\", \"%s\"));
        for k=1:$full_length if(x(k)>$thr_bits) x(k)=x(k)-$max_bits; end; end
        file_id = fopen(\"x$2_$3\", 'w');
        fprintf(file_id,\"%i\\n\",x);
        fclose(file_id);"
    rm $tmp_file
    echo "Decimal $4-bit data writed to x$2_$3 file, $full_length samples."
}

#Use octave for format conversion
case $2 in
    conv)
            data_file_prepare $1 $3 $4 $5
            ;;
    fft)
            data_file_prepare $1 $3 $4 $5
            octave -q --persist --eval "x = load(\"x$3_$4\");
                x_absfft = abs(fft(x));
                f=20*log10(x_absfft/max(x_absfft));
                freq=(1:length(f)/2)*100/(length(f)/2);
                disp(\"To see data type plot(x)\");
                disp(\"To see FFT type plot(freq,f(1:length(f)/2))\");"
            ;;
    *)      use_help
            ;;
esac