Manual

SF11 Laser altimeter
Product manual
5. Menu options
The SF11 can be connected through the on-board USB port to a Terminal emulation program running on a PC. The LightWare Terminal
software is available for download from www.lightware.co.za.
Once the USB connection is made, the Terminal window displays the distance reading from the SF11. The distance, analog voltage or
alarm status and the signal strength are displayed continually in the Terminal window.
Pressing the <SPACE> key stops the measuring process and changes the display to a menu that lists all the available settings and
configuration options. Pressing the <SPACE> key again restarts the measuring process. If no changes are made, the unit will
automatically begin to measure again after two minutes. Many of the menu items can also be changed using the serial port or I2C
command set.
Figure 9 :: LightWare Terminal showing menu options expanded
a: Show or hide the system menu
Menu item <a> is used to expand or hide the system menu. The settings available in this menu relate the zero datum offset and the
measuring mode required to suit a particular application.
b: Zero datum offset (-10.00 m … +10.00 m)
The point from which altitude measurements are taken can be adjusted using menu item <b>. The range of values that can be
entered are from -10.00 meters to +10.00 meters and this value is subtracted from the altitude reading before it is made available
on any of the interfaces. The zero datum offset can be used to compensate for the mounting position of the SF11 in the airframe,
where distance readings may best be interpreted from a suitable point on the landing gear, rather than from the front face of the
SF11.
The zero datum offset can also be changed using the serial port or the I2C command set.
Item
HMI
Type
Serial
I2C
Zero datum offset in meters
menu item <b>
0.56 m
read
?LO<CR><LF>
.write(6) .read(a,b)
?LO 0.35<CR><LF>
zero = (a*256+b)/100
write
#LO,0.56<CR><LF>
.write(7,a,b)
#LO,0.56 0.56<CR><LF>
a = (byte)(zero offset*100 >> 8)
b = (byte)(zero_offset*100 & 0xff)
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