erfan

how can I use the channels 15th and 16th

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Hello ,
on the pixhawk we have 8 channels related to main out (CH1-8) + 6 Aux out (CH9-14).
so in total there is 14 channels. Which I can see the PWM outputs using mission planner when doing radio calibration.

So my question is where are the 15th and 16th channels ? 
and how to assign them to specific command? 


Thanks 

@Spitfire76

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11 hours ago, erfan said:

Hello ,
on the pixhawk we have 8 channels related to main out (CH1-8) + 6 Aux out (CH9-14).
so in total there is 14 channels. Which I can see the PWM outputs using mission planner when doing radio calibration.

So my question is where are the 15th and 16th channels ? 
and how to assign them to specific command? 


Thanks 

@Spitfire76

I believe that they would be available on the sbus output of the pixhawk and you would configure them with SERVO15_FUNCTION and SERVO16_FUNCTION. What exactly do you need to do ?

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5 hours ago, Spitfire76 said:

I believe that they would be available on the sbus output of the pixhawk and you would configure them with SERVO15_FUNCTION and SERVO16_FUNCTION. What exactly do you need to do ?

I want to understand the concept of it.
So you mean there is no physical connection ?

As I understood there is 14 channels on the pixhawk naming (8 main out+ 6 AUX ) I tried also with servo 15 _Function or servo16_function 
but where do I connect the servo for example to check if I get the signal ?

 

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I want to understand the concept of it.
So you mean there is no physical connection ?

As I understood there are 14 channels on the pixhawk naming (8 main out+ 6 AUX ) I tried also with servo 15 _Function or servo16_function 
but where do I connect the servo for example to check if I get the signal from that specific output ?
I would appreciate any idea.
Thanks
@Spitfire76

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7 hours ago, erfan said:

but where do I connect the servo for example to check if I get the signal from that specific output ?

On the side of the flight controller that has the 8 main and 6 aux outputs there should be 2 more connections. One is marked RC which is the sbus connection from the receiver and the other is marked SB which is the sbus out. This should contain all 16 servo function outputs but it has to be connected to a device that understands the sbus protocol. For example I have a camera gimbal that has a controller with a sbus input so can allocate 2 channels to pitch and pan. If you want to control a device that only understands a PWM input you would need to use a sbus to PWM convertor.

So have you used up all 14 PWM outputs ?. Again what are you really trying to configure ?.

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1 hour ago, Spitfire76 said:

On the side of the flight controller that has the 8 main and 6 aux outputs there should be 2 more connections. One is marked RC which is the sbus connection from the receiver and the other is marked SB which is the sbus out. This should contain all 16 servo function outputs but it has to be connected to a device that understands the sbus protocol. For example I have a camera gimbal that has a controller with a sbus input so can allocate 2 channels to pitch and pan. If you want to control a device that only understands a PWM input you would need to use a sbus to PWM convertor.

So have you used up all 14 PWM outputs ?. Again what are you really trying to configure ?.

No I haven’t used all .

I was only curious and wanted to know What and where are the 15.16 channels for.

 

Do you know how  can I use the AUX 5 and 6 to turn on some led lights alternating?

AUX5 and 6 are digital pins.

@Spitfire76

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17 minutes ago, erfan said:

I was only curious and wanted to know What and where are the 15.16 channels for.

Only having 1-14 channels for servo outputs is likely is due to having a limit of 14 PWM outputs on the original Pixhawk hardware (8 main + 6 AUX).

As you may know the 16 channels coming from the receiver need to be allocated to various functions. Some of these functions map to servo functions and some do not. For example RTL does not map to a servo function but needs an input channel from the receiver to trigger it. On the other hand landing gear needs both a channel from the receiver and a servo output. Also rather than just directly mapping a receiver input channel to a servo output (passthru) you may want the flight controller to also control that function. A good example is the case of retractable landing gear as you would likely want it to automatically deploy before it lands in the case of RTL or have a mission script control that function. So don't think of the servo output functions correspond to the receiver input channel as they are really separated. 

53 minutes ago, erfan said:

Do you know how  can I use the AUX 5 and 6 to turn on some led lights alternating?

AUX5 and 6 are digital pins.

These should by default (BRD_PWM_COUNT = 4) be assigned as digital output rather than PWM servo functions outputs which by the way also means that servo channels 13 and 14 and not used by default in addition to 15 and 16. in this case aux5 and 6 correspond to the first and second relays and can be operated by a receiver channel or a mission script. 

http://ardupilot.org/copter/docs/common-relay.html

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So you mean when a flight controller wants to control a function (rectractable  landing gear) Then a servo*_function needs to be mapped ,right?

Now the question is in case of triggering any mode forexample RTL or AUTO 

the mission or the location is saved inside the SD card of the flight controller , why we only map them only to a input channel from receiver? 

@Spitfire76

 

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16 hours ago, Spitfire76 said:

These should by default (BRD_PWM_COUNT = 4) be assigned as digital output rather than PWM servo functions outputs which by the way also means that servo channels 13 and 14 and not used by default in addition to 15 and 16. in this case aux5 and 6 correspond to the first and second relays and can be operated by a receiver channel or a mission script. 

http://ardupilot.org/copter/docs/common-relay.html

I have set BRD_PWM_COUNT=4 

meaning the AUX 5 and 6 are as relays .

I have also mapped channel 6 ad relay on and off.

additionally, I have power up the flight controller from the behind( servos)

But as I check the voltage on the relay (AUX5 and 6) and change the switch on the transmitter.

the voltage is no voltage change!?

how can I check if this is working fine or not?

Thanks

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6 hours ago, erfan said:

So you mean when a flight controller wants to control a function (rectractable  landing gear) Then a servo*_function needs to be mapped ,right?

Let's take a step back and continue to use the retractable landing gear as an example as I've had experience in setting that up. Firstly you have to of course know what is type of signal is required by the landing gear hardware for it to deploy and retract. In my case the landing gear controller required a PWM signal. Originally I did not have this driven from the flight controller but simply use one of the spare PWM outputs of the receiver which was in turn mapped to a switch on my transmitter. This worked but what would have happened if my drone lost the transmitter signal and the failsafe action was RTL  or land ?. If the landing gear was retracted when this occurred there is no way to deploy it before it landed unless I could regain control over the drone. So this is the case when you want the flight controller to drive the PWM to the landing gear controller as the ArdCopter code does deploy it before it lands. Of course you also want to retract and deploy it from a switch on the transmitter. I used the first aux pins and so SERVO9_FUNCTION was set to landing gear and also CHXX_OPT was set to landing gear where XX was the sbus channel I was using from the receiver. 

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12 hours ago, erfan said:

I have also mapped channel 6 ad relay on and off.

I don't see how you could have used channel 6. My understanding is that you have to use channels 7 - 12. 7 & 8 can be set from MP's extended tuning screen and you should see in the drop down Relay on/off which would correspond to aux 5 and relay 1 aux 6. 

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