diff --git a/bin/device-install.sh b/bin/device-install.sh
index 1101e26b..fb374d09 100755
--- a/bin/device-install.sh
+++ b/bin/device-install.sh
@@ -1,11 +1,45 @@
-#!/bin/bash
+#!/bin/sh
 
-set -e
+# Usage info
+show_help() {
+cat << EOF
+Usage: ${0##*/} [-h] [-p ESPTOOL_PORT] [-f FILENAME]
+Flash image file to device, but first erasing and writing system information"
 
-FILENAME=$1
+    -h               Display this help and exit
+    -p ESPTOOL_PORT  Set the environment variable for ESPTOOL_PORT.  If not set, ESPTOOL iterates all ports (Dangerrous).
+    -f FILENAME         The .bin file to flash.  Custom to your device type and region.
+EOF
+}
 
-echo "Trying to flash $FILENAME, but first erasing and writing system information"
-esptool.py --baud 921600 erase_flash
-esptool.py --baud 921600 write_flash 0x1000 system-info.bin
-esptool.py --baud 921600 write_flash 0x10000 $FILENAME
 
+while getopts ":h:p:f:" opt; do
+    case "${opt}" in
+        h)
+            show_help
+            exit 0
+            ;;
+        p)  export ESPTOOL_PORT=${OPTARG}
+	    ;;
+        f)  FILENAME=${OPTARG}
+            ;;
+        *)
+ 	    echo "Invalid flag."
+            show_help >&2
+            exit 1
+            ;;
+    esac
+done
+shift "$((OPTIND-1))"
+
+if [ -f "${FILENAME}" ]; then
+	echo "Trying to flash ${FILENAME}, but first erasing and writing system information"
+	esptool.py --baud 921600 erase_flash
+	esptool.py --baud 921600 write_flash 0x1000 system-info.bin
+	esptool.py --baud 921600 write_flash 0x10000 ${FILENAME}
+else
+	echo "Invalid file: ${FILENAME}"
+	show_help
+fi
+
+exit 0
diff --git a/bin/device-update.sh b/bin/device-update.sh
index ecfee105..4125ade6 100755
--- a/bin/device-update.sh
+++ b/bin/device-update.sh
@@ -1,8 +1,43 @@
-#!/bin/bash
+#!/bin/sh
 
-set -e
+# Usage info
+show_help() {
+cat << EOF
+Usage: ${0##*/} [-h] [-p ESPTOOL_PORT] -f FILENAME
+Flash image file to device, leave existing system intact."
 
-FILENAME=$1
+    -h               Display this help and exit
+    -p ESPTOOL_PORT  Set the environment variable for ESPTOOL_PORT.  If not set, ESPTOOL iterates all ports (Dangerrous).
+    -f FILENAME         The .bin file to flash.  Custom to your device type and region.
+EOF
+}
 
-echo "Trying to update $FILENAME"
-esptool.py --baud 921600 write_flash 0x10000 $FILENAME
+
+while getopts ":h:p:f:" opt; do
+    case "${opt}" in
+        h)
+            show_help
+            exit 0
+            ;;
+        p)  export ESPTOOL_PORT=${OPTARG}
+	    ;;
+        f)  FILENAME=${OPTARG}
+            ;;
+        *)
+ 	    echo "Invalid flag."
+            show_help >&2
+            exit 1
+            ;;
+    esac
+done
+shift "$((OPTIND-1))"
+
+if [ -f "${FILENAME}" ]; then
+	echo "Trying to flash update ${FILENAME}."
+	esptool.py --baud 921600 write_flash 0x10000 ${FILENAME}
+else
+	echo "Invalid file: ${FILENAME}"
+	show_help
+fi
+
+exit 0