Ltspice
From Attie's Wiki
(Difference between revisions)
(Created page with "==Using a captured waveform as LTspice input== This outlines the steps necessary to use a CSV file as input for LTspice. ==Capture your waveform== I have captured the followi...") |
m (→Convert the CSV file to a RAW 8-bit file) |
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==Convert the CSV file to a RAW 8-bit file== | ==Convert the CSV file to a RAW 8-bit file== | ||
| − | Use the | + | Use the script below. |
| + | There are a few configuration options: | ||
| + | {| | ||
| + | ! Option Name !! Description | ||
| + | |- | ||
| + | | CSV_FILE || The source CSV file | ||
| + | |- | ||
| + | | CSV_COLUMN || The column of the CSV file that you'd like to extract | ||
| + | |- | ||
| + | | SAMPLE_RATE || The rate that the samples were stored at, in Hz | ||
| + | |- | ||
| + | | ROOT_FILENAME || <i>(optional)</i> If you want to store the output somewhere else, then change this | ||
| + | |} | ||
| + | |||
<source lang="bash"> | <source lang="bash"> | ||
#!/bin/bash -e | #!/bin/bash -e | ||
| Line 28: | Line 41: | ||
CSV_FILE=loaded.csv | CSV_FILE=loaded.csv | ||
CSV_COLUMN=2 | CSV_COLUMN=2 | ||
| + | |||
| + | SAMPLE_RATE=500000 | ||
ROOT_FILENAME=$(echo ${CSV_FILE} | rev | cut -d . -f 2- | rev) | ROOT_FILENAME=$(echo ${CSV_FILE} | rev | cut -d . -f 2- | rev) | ||
| Line 44: | Line 59: | ||
| tee .${CSV_FILE}.normal \ | | tee .${CSV_FILE}.normal \ | ||
| sort -n \ | | sort -n \ | ||
| − | + | | uniq \ | |
> .${CSV_FILE}.sorted | > .${CSV_FILE}.sorted | ||
| − | + | ||
cat .${CSV_FILE}.sorted | sed -n "1p;$(wc -l .${CSV_FILE}.sorted | cut -d ' ' -f 1)p" > .${CSV_FILE}.extremes | cat .${CSV_FILE}.sorted | sed -n "1p;$(wc -l .${CSV_FILE}.sorted | cut -d ' ' -f 1)p" > .${CSV_FILE}.extremes | ||
| Line 70: | Line 85: | ||
| awk '{printf "%c", strtonum($0)}' \ | | awk '{printf "%c", strtonum($0)}' \ | ||
> ${ROOT_FILENAME}.raw | > ${ROOT_FILENAME}.raw | ||
| + | |||
| + | DATA_SIZE=$(stat -c%s ${ROOT_FILENAME}.raw) | ||
| + | CHUNK_SIZE=$((DATA_SIZE + 36)) | ||
| + | |||
| + | WAV=${ROOT_FILENAME}.wav | ||
| + | |||
| + | # writeNumAsBin | ||
| + | # arg1: bytes used to represent the word | ||
| + | # arg2: value stored in the word | ||
| + | function wnab() { | ||
| + | WORD_SIZE=$1; shift | ||
| + | WORD_VALUE=$1; shift | ||
| + | printf "%0$((WORD_SIZE * 2))x" ${WORD_VALUE} \ | ||
| + | | fold -w2 \ | ||
| + | | sed '1!G;h;$!d' \ | ||
| + | | awk '{printf "%c", strtonum($0)}' | ||
| + | } | ||
| + | |||
| + | truncate -s0 ${WAV} | ||
| + | |||
| + | # ChunkID | ||
| + | echo "RIFF" >> ${WAV} | ||
| + | # ChunkSize | ||
| + | wnab 4 ${CHUNK_SIZE} >> ${WAV} | ||
| + | # Format & Subchunk1ID | ||
| + | echo "WAVEfmt " >> ${WAV} | ||
| + | # Subchunk1Size | ||
| + | wnab 4 16 >> ${WAV} | ||
| + | # AudioFormat | ||
| + | wnab 2 1 >> ${WAV} | ||
| + | # NumChannels | ||
| + | wnab 2 1 >> ${WAV} | ||
| + | # SampleRate | ||
| + | wnab 4 ${SAMPLE_RATE} >> ${WAV} | ||
| + | # ByteRate | ||
| + | wnab 4 ${SAMPLE_RATE} >> ${WAV} | ||
| + | # BlockAlign | ||
| + | wnab 2 1 >> ${WAV} | ||
| + | # BitsPerSample | ||
| + | wnab 2 8 >> ${WAV} | ||
| + | # Subchunk2ID | ||
| + | echo "data" >> ${WAV} | ||
| + | # Subchunk2Size | ||
| + | wnab 4 ${DATA_SIZE} >> ${WAV} | ||
| + | # data! | ||
| + | cat ${ROOT_FILENAME}.raw >> ${WAV} | ||
</source> | </source> | ||
| + | |||
| + | Useful resources: | ||
| + | * https://ccrma.stanford.edu/courses/422/projects/WaveFormat/ | ||
Revision as of 18:17, 5 October 2013
Using a captured waveform as LTspice input
This outlines the steps necessary to use a CSV file as input for LTspice.
Capture your waveform
I have captured the following waveform using my scope, and saved it as a CSV file.
A sample of the CSV file is shown below:
x-axis,3,D0-D7 second,Volt, -1.0000000E-03,-48.2407212E-03,0 -999.8000E-06,-48.2407212E-03,0 -999.6000E-06,-48.2407212E-03,0 -999.4000E-06,-48.2407212E-03,0 - - - - - - - - >8 - - - - - - - - +8.9990000E-03,-168.8437350E-03,0 +8.9992000E-03,-176.8839359E-03,0 +8.9994000E-03,-48.2407212E-03,0 +8.9996000E-03,-48.2407212E-03,0
Convert the CSV file to a RAW 8-bit file
Use the script below. There are a few configuration options:
| Option Name | Description |
|---|---|
| CSV_FILE | The source CSV file |
| CSV_COLUMN | The column of the CSV file that you'd like to extract |
| SAMPLE_RATE | The rate that the samples were stored at, in Hz |
| ROOT_FILENAME | (optional) If you want to store the output somewhere else, then change this |
#!/bin/bash -e CSV_FILE=loaded.csv CSV_COLUMN=2 SAMPLE_RATE=500000 ROOT_FILENAME=$(echo ${CSV_FILE} | rev | cut -d . -f 2- | rev) # end of configuration cat ${CSV_FILE} \ | tail -n+3 \ | cut -d , -f ${CSV_COLUMN} \ | sed -r \ -e 's/^\+//' \ -e 's/^(-?[0-9]+\.[0-9]+)[eE]([+-])([0-9]+)$/\1*(10^\2\3)/' \ -e 's/\*\(10\^\+00\)$//' \ | bc -l \ | sed -re 's/^(-?)\./\10./' \ | tee .${CSV_FILE}.normal \ | sort -n \ | uniq \ > .${CSV_FILE}.sorted cat .${CSV_FILE}.sorted | sed -n "1p;$(wc -l .${CSV_FILE}.sorted | cut -d ' ' -f 1)p" > .${CSV_FILE}.extremes LO=$(cat .${CSV_FILE}.extremes | head -n 1) if [ $(echo "${LO} < 0" | bc) == "1" ]; then OP=- else OP=+ fi HI=$(echo "($(cat .${CSV_FILE}.extremes | tail -n 1))${OP}(${LO})" | bc -l) ML=$(echo "255/${HI}" | bc -l) cat .${CSV_FILE}.normal \ | sed -r \ -e 's/^/((/' \ -e 's/$/)/' \ -e "s/$/${OP}(${LO})/" \ -e "s/$/)*${ML}/" \ | bc -l \ | sed -r \ -e 's/^([0-9]*).([0-9]?[0-9]?[0-9]?).*$/\1.\2/' \ | tee .${CSV_FILE}.adjusted \ | awk '{printf "%c", strtonum($0)}' \ > ${ROOT_FILENAME}.raw DATA_SIZE=$(stat -c%s ${ROOT_FILENAME}.raw) CHUNK_SIZE=$((DATA_SIZE + 36)) WAV=${ROOT_FILENAME}.wav # writeNumAsBin # arg1: bytes used to represent the word # arg2: value stored in the word function wnab() { WORD_SIZE=$1; shift WORD_VALUE=$1; shift printf "%0$((WORD_SIZE * 2))x" ${WORD_VALUE} \ | fold -w2 \ | sed '1!G;h;$!d' \ | awk '{printf "%c", strtonum($0)}' } truncate -s0 ${WAV} # ChunkID echo "RIFF" >> ${WAV} # ChunkSize wnab 4 ${CHUNK_SIZE} >> ${WAV} # Format & Subchunk1ID echo "WAVEfmt " >> ${WAV} # Subchunk1Size wnab 4 16 >> ${WAV} # AudioFormat wnab 2 1 >> ${WAV} # NumChannels wnab 2 1 >> ${WAV} # SampleRate wnab 4 ${SAMPLE_RATE} >> ${WAV} # ByteRate wnab 4 ${SAMPLE_RATE} >> ${WAV} # BlockAlign wnab 2 1 >> ${WAV} # BitsPerSample wnab 2 8 >> ${WAV} # Subchunk2ID echo "data" >> ${WAV} # Subchunk2Size wnab 4 ${DATA_SIZE} >> ${WAV} # data! cat ${ROOT_FILENAME}.raw >> ${WAV}
Useful resources:
