onerng.sh

onerng.sh

#!/bin/bash
ONERNG=/dev/ttyACM0
t=onerng.out

stty -F $ONERNG raw -echo clocal -crtscts
echo "cmd0" >$ONERNG            # standard noise
echo "cmdO" >$ONERNG            # turn it on
stty -F $ONERNG raw -echo clocal -crtscts
gone() {
echo "cmdo" >$ONERNG            # turn it off
echo "cmd4" >$ONERNG            # turn off noise gathering
echo "cmdw" >$ONERNG            # flush entropy pool
}
trap gone EXIT SIGINT SIGTERM SIGHUP
dd if=$ONERNG iflag=fullblock bs=1k "$@"
exit 0