Author: Guido Socher <>
Copyright: GPL

To "talk" to the Linux LCD panel you need to:
1) initialize the serial line 
   ttydevinit /dev/ttyS0      (for com1)
2) open 2 xterm windows. In one you type
  cat /dev/ttyS0
   in the other you type
  cat > /dev/ttyS0
  Now you can type commands e.g l=11 and you can see
  the answers from the microcontroller in the first xterm window.

Linux LCD panel command language

The file describes the command language that the Linux LCD panel
understands. Although this is human readable and ASCII based, the
software on the controller is not checking for all kind of
syntax errors. The is not enough ram on the AVR to implement a full
blown parser. The commands are primarily designed as a machine
to machine language where typing and syntax errors will not occur.

valid command are:
   l=10 led 1 off
   l=11 led 1 on
   l=00 led 0 off
   l=01 led 0 on
   b=1 send info about button press. The messages at button press
   are #0 for button 0 and #1 for button 1
   b=0 stop sending info about button press.
   b=? print b:1 if button info is on or b:0 if it is off.
   d=somestring send a string of max 20 character to the lcd
   D=somestring same as d=somestring but clear the display first
   g=yx go to position y,x on the display. E.g g=010 will go
   to line 0 (y) and character position 10 (x)
   lcd control commands
     c=c clear display
     c=h home
     c=r one right
     c=l one left
     c=b blink cursor
     c=n normal cursor
   a=0 read the data from ADC-0 (ADC=Analog to Digital Converter).
   Watchdog commands
    w=1 enable watch dog
    w=2 enable watch dog, and set timeout to 110 (~30 minutes)
        at every D= or d= command (autokick watchdog)
    w=0 disable watch dog
    w=? show whether wd is on or off and if there was a timeout
        before. (off=0, on=1, on and autokick=2, off and prev. timeout=3) 
    w=s get current time out
   Set the watch dog timeout (kick the watch dog).
   You need to call this command periodically if the watch dog
   is on (except if w=2).
   s=255 will set the watch dog to 255. The watchdog counts down
   by one unit approx. very 16 sec. The value range for s is 1-255.

   The watch dog will toggle the relai only once. After that it is
   off again. This it to avoid that the watch dog hits during a file
   system check.