User Manual

Switch 6: R/C Failsafe Timeout
In all the R/C modes, if switch 6 is set to the UP position,
then Timeout Failsafe mode is active. This will bring the
motor to a stop if the servo signal is interrupted. Once
several valid control signals are sent, the motor will restart.
This is useful to prevent to robot driving away if it
encounters interference, drives out of range, or if the transmitter is inadvertently de-activated.
Many robot competitions require this feature.
If switch 6 is set in the DOWN position, then Timeout Failsafe mode is de-activated. This means
that the SyRen will continue to drive the motor according to the last command until another
command is given. If the control link is possible unreliable – like a radio - then this can be
dangerous due to the robot not stopping. However, it is extremely convenient if you are
controlling the SyRen from a microcontroller. In this case, commanding the controller can be
done with as little as three lines of code.
Output_High(Pin connected to S1)
Delay(1000us to 2000us)
Output_Low(Pin connected to S1)
This makes it easy to use R/C mode without having to set up a repeating pulse stream. This is
most advantageous on controllers like Basic Stamps, which don’t have the ability to perform
background tasks.
A note on certain microprocessor receivers
Some receivers, such as the Spektrum AR6000, will output servo pulses before a valid
transmitter signal is present. This will cause the SyRen to autocalibrate to the receiver’s startup
position which may not correspond to the center stick position, depending on trim settings. This
may cause the motors to move slowly, even when the transmitter stick is centered. If you
encounter this, either consult your receiver manual to reprogram the startup position, or adjust
your transmitter trims until the motors stop moving. As a last resort, you can enter R/C
microcontroller mode which will disable SyRen’s autocalibration.
R/C Failsafe Timeout Disabled