A simple binary clock

binary-clock.sh

#!/bin/bash -

SCRIPT: binary-clock
AUTHOR: Luciano D. Cecere
YEAR: 2016

PROGRAM="${0##*/}"

format="\n\t%s\t%s\n"

_dec_to_bin()
{
	local decimal=$1
	local bit binary

	while [ $decimal -ne 0 ]
	do
		((bit=decimal % 2))
		binary=$bit$binary
		((decimal/=2))
	done

	while ((${#binary} < 9))
	do
		binary="0$binary"
	done

	echo $binary | sed "s/0/     /g" | sed "s/1/  0  /g"
}

_get_hour() { date +%_$x; }

_get_minute() { date +%_M; }

_get_second() { date +%_S; }

_clock()
{

	while clear
	do
		local h=$(_get_hour)
		local m=$(_get_minute)
		local s=$(_get_second)
		printf "\n\n"
		printf "$format" "$(_dec_to_bin $h)" "$h"
		printf "$format" "$(_dec_to_bin $m)" "$m"
		printf "$format" "$(_dec_to_bin $s)" "$s"
		printf "\n\t\t%s\n" "        32   16    8    4    2    1"
		sleep 1
	done

}

case $1 in
	-h)
		echo "Usage: $PROGRAM [12 24 -h]"
		exit
		;;
	24)
		x=H
		;;
	12|*)
		x=I
		;;
esac

trap 'printf "\e[?12l\e[?25h"' EXIT

printf "\e[?25l"

_clock