1 files changed, 47 insertions, 0 deletions
diff --git a/recipes-demo/de10-nano-gpio-apps/files/watch_switch_events.sh b/recipes-demo/de10-nano-gpio-apps/files/watch_switch_events.sh
new file mode 100755
index 0000000..978706d
--- /dev/null
+++ b/recipes-demo/de10-nano-gpio-apps/files/watch_switch_events.sh
@@ -0,0 +1,47 @@
+#$/bin/sh
+
+#open the input event device for our gpio-keys
+exec 7<>/dev/input/by-path/platform-soc:base-fpga-region:keys-event
+
+# start a subshell with the output from the device file as its input
+(
+	# loop forever
+	while [ true ]
+	do
+
+	# get the next 16 byte event data, then extract the three hex strings
+	# for type, code and value in little endian form and convert each value
+	# to a decimal representation
+	SAMPLE="$(dd bs=16 count=1 2> /dev/null | hexdump -v -e '16/1 "%02x "' -e '"\n"' | sed -e "s/.*\s.*\s.*\s.*\s.*\s.*\s.*\s.*\s\(.*\)\s\(.*\)\s\(.*\)\s\(.*\)\s\(.*\)\s\(.*\)\s\(.*\)\s\(.*\)/0x\2\1 0x\4\3 0x\8\7\6\5/")"
+	SAMPLE_TYPE="$(printf "%d" "$(echo ${SAMPLE} | cut -d ' ' -f 1)")"
+	SAMPLE_CODE="$(printf "%d" "$(echo ${SAMPLE} | cut -d ' ' -f 2)")"
+	SAMPLE_VALUE="$(printf "%d" "$(echo ${SAMPLE} | cut -d ' ' -f 3)")"
+
+	# if the sample type is EV_KEY, then process it, otherwise ignore it
+	[ "${SAMPLE_TYPE}" -eq "1" ] && {
+
+		# look for the codes that we expect
+		case "${SAMPLE_CODE}" in
+			64)
+				echo -n "SW0"
+				;;
+			65)
+				echo -n "SW1"
+				;;
+			66)
+				echo -n "SW2"
+				;;
+			67)
+				echo -n "SW3"
+				;;
+			*)
+				echo -n "unknown"
+				;;
+		esac
+
+		# output the value of the event
+		echo " moved to value '${SAMPLE_VALUE}'"
+	}
+	done
+) <&7
+