reliably power cycle arduino nano

added enough timeouts to wait for startup message and then pull
relay pin low for 3s before letting it float again

diff --git a/power_cycle/power_cycle.sh b/power_cycle/power_cycle.sh
new file mode 100755 (executable)
index 0000000..da91d03
--- /dev/null
+++ b/power_cycle/power_cycle.sh
@@ -0,0 +1,19 @@
+#!/bin/sh -xe
+
+dev=/dev/ttyUSB4
+
+trap "exit" INT TERM
+trap "kill 0" EXIT
+
+stty -F $dev speed 115200 raw
+cat < $dev &
+(
+       echo
+       sleep 3
+        echo 0
+        sleep 3
+        echo 1
+        sleep 1
+) | cat > $dev
+
+kill $!