I understand that the PWM output from the K8055 kit has a fixed frequency of 23kHz.
Is it possible to change any of the components on the board in order to adjust this down to around 50Hz, so that the PWM output would then be suitable for controlling servo motors?
Sorry, it is not possible. The PWM frequency is hard-coded to the firmware of the microcontroller.
I’m very disappointed that the K8055 PWM outputs can’t be used to control rc-servos.
It would be nice if Velleman could add this feature to the firmware.
Could you please describe the control voltage sequence of the timing for the servo.
Then I’ll check if it is possible with the K8055.
VEL255 Thank you for interest.
RC-Servos are wildly used for teaching robotic.
nominal pulse width varies from 1 - 2ms where 1.5ms is the neutral (middle) position. See top of mp.ttu.ee/risto/rc/electroni … signal.htm
BTW I bought the K8055 to evaluate it for the practical part of our electronic course for Ph.D. Students[/quote]
At 23kHz, maybe the K8055 could at least support 23 steps (or half/double, depending on OCC design)? Never tried that K8055 PWM, but being a R/C model airplaner, doesn’t it need inverting? Airplans always do… But then, I’m always inverted!?
Sorry, but the K8055 is too slow to output 1…2ms pulses.
The update rate is defined by the USB standard and is 10ms.
i have another idea about controling servos with the k8055:
the problem is that the frecuency of the k8055 is 23khz and is fixed.
but the frecuency of the servo?
maybe can there is a solution that is change the frequency of the servo.
Any update on how to connect a servomotor to the board?
And if there is no way to connect one, wich can of output device can be connected to the K8055 board?
i found this link that shows the simple, fast, cheap (4 euros!!) way of connecting a 5vdc RC servo to a proportionnal dc signal like the k8055 is giving as output. 
epanorama.net/circuits/servo10v.html
just replace the input resistors 100k and 47k by a potentiometer (or variable resistance) of 220k or less to compatibilise the sheme with 5vdc input once calibrated correctly.
I can confirm this works: find modified plan here :
mczouav.blogspot.com/2009/10/kit … pling.html
the tested servo was able to move over 120 degrees.
mc 