UMAX130511 Version 1.00A Preliminary Documentation
– May be subject to change
28 - 141
Figure 12
– Analog Output Logic Flowchart
In addition to the read-only mappable object 7330h
AO Output Field Value
(as represented by the
green box above), there is another object 2370h
AO Feedback FV
, also read-only mappable. This
object reflects the actual measured value at the output. It is also used to detect and flag an error if
there is an open or short circuit at the output.
If object 2310h
AO Error Detect Enable
is set to TRUE, then the absolute value between the
desired output FV (7330h) and the measured feedback (2370h) is compared to 2311h
AO Error
Clear Hysteresis
. If the difference between the target and the actual exceeds the hysteresis value,
then a fault is present. Since both open and short circuits read close to zero feedback, a signal is
also sent to the processor whenever a short (to either GND or +Vcc) has occurred.