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SF02/F
SF02/F
Laser rangefinder
Product manual
Alarms
e: Alarm 1 distance (0.00m to 50.00m) - Sets the distance at which the first alarm activates
f: Alarm 2 distance (0.00m to 50.00m - Sets the distance at which the second alarm activates
(available on the digital expansion port only)
g: Alarm 3 distance (0.00m to 50.00m) - Sets the distance at which the third alarm activates
(available on the digital expansion port only)
h: Alarm hysteresis (0.00m to 1.00m) - Creates a dead-band between the on and off points of the alarms
A digital alarm output goes high whenever an object is detected that is closer than the distance setting shown in menu items <e>,
<f> and <g>. This distance can be set from 0.00 meters to 50.00 meters and each alarm output is updated 32 times per second. To
prevent multiple switching of the alarm output, menu item <h> provides for hysteresis on the alarm distances. This will change the
alarm activation and deactivation distances to:
activation distance = alarm distance - hysteresis
deactivation distance = alarm di hysteresis
The hysteresis can be adjusted up to ±5.00 meters.
Figure 18 :: Ground proximity alarm warning
Auxiliary UART
i: Serial port baud rate (4800 ... 115200) - Selects the baud rate of the auxiliary serial port UART channel
The auxiliary serial port, or UART, transmits a serial string of ASCII encoded data from the SF02/F to the host controller. The baud
rate of transmission is selected by menu item <i> and can be any of the standard baud rates from 4800 to 115200. By default, there
is one stop bit and no parity or handshaking on this serial port.
The ASCII string representing the distance is in fixed point format with two decimal places followed by carriage return and line feed,
as follows:
“22.48\r\n”
where carriage return and line feed are given by the hexadecimal ASCII characters:
\r
=
0x0D
\n
=
0x0A
Data is sent out of the auxiliary serial port whenever a “trigger” notification is received. The ASCII character <D> acts as a trigger
when transmitted by the host controller to the SF02/F. Additionally, there is a falling edge, hardware trigger that can be controlled
by a digital port pin on the host controller.
Auxiliary bus port (I2C)
j: I2C bus address (0 … FF) - Sets the auxiliary I2C address (available on the digital expansion port only)
There is an I2C bus available for systems where bus communication is used to reduce the number of ports required for
communication. The address can be set using menu option <j> and the maximum latency is 60 ms.
The host controller acts as the I2C “master” and sends the address to the SF02/F as an 8 bit value (7 address bits plus 1 read bit).
The SF02/F then returns the distance as a 16 bit integer, formatted as high byte followed by low byte in centimetres.
SF02/F Laser Rangefinder - Product Manual - Revision 10
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© LightWare Optoelectronics (Pty) Ltd, 2016
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