little device (MSP430F1xxx) decodes a R/C servo signal and offers a
special kind of sequential logic switch (on/off switch).
There are two options :
OPT1 : 0 : Output high if servo signal < 1.20ms
1 : Output high
if servo signal > 1.80ms OPT2 : 0 : Output high any time the RC receiver delivers a signal as selected by OPT1.
1 : Output high, just any
second time the RC receiver delivers a signal as described
GPS-Landing ___________________|XXXXX|_____________________________________|XXXXXXXX OPT2 = 1 (both units can be turned off)
GPS-Landing ___________________|XXXXX|_______________|XXXXX|_____________|XXXXXXXX OPT2 = 0 (one unit is always working)
Option OPT2 = 1 allows turn on and off two units by a single RC-channel independently.
For example if a variometer and a GPS supported landing system should be controlled via a
single channel. The variometer is used during regular flight, the GPSL system is just needed
If the variometer is directly connected to the RC receiver (transmitting if servo signal > 1.8ms)
and the GPS-landing system is connected via a Y-cable and via the RCS device (with settings
OPT1 = 0 and OPT2 = 1), both units can be activated alternatively by a single RC channel.
The everage power is less than 1mA.
The output is availabe as a true and an inverted signal.
Additionally a 31.5 kHz signal is generated to feed external devices (e.g. a pressure sensor).
Here the schematic , just an example how to connect the device (pdf)
The code can be found here.