value() from AnalogOutput

Hello,

When I set an AnalogOutput with a value and I do a read afterwards with value(), I get the right value. When I do a read some time afterwards, I get a complete wrong value. However when I measure the analog line with a scope I have a straight line (so no value changed). How does this come ?

Stefaan

value() from AnalogOutput

> Hello,
>
> When I set an AnalogOutput with a value and I do a read afterwards with
> value(), I get the right value. When I do a read some time afterwards, I
> get a complete wrong value. However when I measure the analog line with a
> scope I have a straight line (so no value changed). How does this come ?

The AnalogOutput reads the data back from the (Comedi) analog output
subdevice, which reads it in turn directly from the card. If reading
fails,
an uninitialised value is returned from AnalogOutput. This should be fixed.

So the conclusion is that 'after some time' the driver could no longer
read your subdevice. You could validate this with a comedi_inp and check
the value of the channel when this happens. If comedi_inp returns a
correct value, something is fishy in the Orocos layer.

Peter

>
> Stefaan
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