diff --git a/LINUX.md b/LINUX.md
index c161952..8e625eb 100644
--- a/LINUX.md
+++ b/LINUX.md
@@ -7,38 +7,50 @@ which made it difficult to use on Linux systems
 This version of the firmware has been modified to support Linux systems.
 The following changes have been made
 - The backspace key works during the GUI login
-- The Sym key not acts as a Control key, so SYM+C is Control-C
+- The Sym key now acts as a Control key, so SYM+C is Control-C
 - The four top button keys are now used to provide the missing characters.
 
-The original definiton of the keys were this 
+The original definiton of the keys were this. I'm including the
+spacebar, newline/enter, backspace, Microphone and Spkeaer keys
+because they provide characters not indicated on the key. For
+instance, SYM + spacebar provides TAB
+
 
 |      | L1    | L2    |    R1 |    R2 | SPKR | Mic| BS | NL |  SPACE  |
 | ------|-------|-------|-------|-------|------|----|---|---|---------|
-| none  |       |       |       |       |  $   |  ~ | \b| \n| space   |
+| none  |       |       |       |       |  $   |  ~ | \b| \n| SPACE   |
 | Alt   |       |       |       |       |  \`  |  0 |   |   |         |
 | Shift |       |       |       |       |  $   |    |   |   |         |
-| Sym   |       |       |       |       |  $   |    |   |\| |  tab    |
+| Sym   |       |       |       |       |  $   |    |   |\| |  TAB   |
 
 
 
 This firmware adds the following mappings
 
+
 |      | L1     | L2    |    R1 |    R2 | SPKR | Mic| BS| NL|  SPACE  |
 | ------|--------|-------|-------|-------|------|----|---|---|---------|
-| none  | escape |  %    |  =    |  \\   |  $   |  ~ | \b| \n| space |
+| none  | escape |  %    |  =    |  \\   |  $   |  ~ | \b| \n| SPACE |
 | Alt   |  >     |  ]    |  }    |  &    |  \`  |  0 |   |   |         |
 | Shift |  <     |  ]    |  {    |  ^    |  $   |  ~ | \b|   |         |
-| Sym   |        |       |       |       |  $   |  ~ | \b|\| |  tab  |
+| Sym   |        |       |       |       |  $   |  ~ | \b|\| |  TAB |
 
 ## Linux Debug tips
 
-The keyboard was two "outputs" - one is the USB HID interface, the other is the serial port.
-Any printf() command goes to the serial port.
+The keyboard has two "outputs" - one is the USB HID interface, the
+other is the serial port.  Any printf() command goes to the serial
+port, but not the USB HID keyboard. For instance, when using an
+Arduino sketch, print() goes to the serial port.
 
-When the keyboard is plugged into a Linux system, a new TTY interface will appear. I usually use "ls -lt /dev/tty* | head"
-to learn the name, as the newest port will appear first. On my system, it's /dev/ttyACM0
+When the keyboard is plugged into a Linux system, a new TTY interface
+will appear. I usually use 
 
-So on one terminal, I type
+	ls -lt /dev/tty* | head" 
+ 
+to learn the name, as the newest port will appear first. On my system,
+it's /dev/ttyACM0
+
+So on one terminal window, I type
 
     cat -v </dev/ttyACM0
 
@@ -46,11 +58,15 @@ while on a second terminal window, I type
 
     cat -v
 
-The first one will print all of the printf output, and the second will show you how the keyboard works normally.
+The first one will print all of the printf output, and the second will
+show you how the keyboard works normally and what gets sent to the USB
+keyboard when a key is pressed..
 
 ## Compiling firmware on Linux
 
-I edit the files in <GIT>/ic2_puppet/all/ using my preferred editor. In my case, I use emacs. I have the keystroke combination "Control-C M" bound to compile, using 
+I edit the files in <GIT>/ic2_puppet/all/ using my preferred
+editor. In my case, I use emacs. I have the keystroke combination
+"Control-C M" bound to compile, using
 
     (global-set-key "\C-cm" 'compile)
 
@@ -59,6 +75,11 @@ code. I have a small hub with switchable on/off ports, and restart the
 keyboard into boot mode, and then do a "make install" to load the new
 firmware
 
+## GUI Login
+
+I found that I had to handle the backspace differently, as arturo did
+for enter. This was necessary so that the backspace key would delete
+the username or password characters.
 
 ## TODO