Have a look into the AMuxHw datasheet: on page 1 it is stated that the inputs must be GPIO pins.
I have tried to ise GPIO as inputs on the AMuxHW and got the same error. I have placed a GPIOs at the output of the AMuxHW and input of ADC, and I got a message " Either the design is bigger than this chip can handle, or the design is over-constrained and there are not enough resources to satisfy the constraints."
Additionally I have discarded the AMuxHW as a whole and used the AMux built into the ADC, and got the same message - "Unable to find a solution for the analog routing."
I think that this has to do with the attempt to use all OPAmps and Comparators of the chip, and there is not enough routing resources to do that. Do you think that this is the case? The only reason I am using an op-amp is to condition the signals, since they require a high impedance inputs (the sensor is a piezo film and is described as an ideal voltage source).
Any help or ideas will be greatly appreciable.
Problem solves when deleting the 2 OpAmps from the design. It seems to me that they share the same route with the vplus bus of the LPComparators, which is strange, since they are available as separate resources, but can't be used be used together.
Any thoughts on that?