I can't perform analog output with the MX100/DARWIN API.

For user analog output on the MX100, set the AO module channel to command AO, and send the AO data.

• Set the channel to command AO
  See the setup change function of the setting function (setAOTypeMX)
  For extended API, see channel settings (setChKindMX100)
• Preparing AO data
  See the setup change functions (changeAOPWMDataMX)
  For the extended API, see the data manipulation functions (createAOPWMMX100,changeAOPWMMX100)
• Sending AO data
  See the collective setting functions of the setting function (setAOPWMDataMX)
  For the extended API, see the data manipulation functions (commandAOPWMMX100)

This is also the same for PWM. See functions for settings (setPWMTypeMX). Value specified on instrument (output data value) differs from actually output value (actual output value). See the conversion utility functions.
Chapter, "Correspondence between Functions and Class/Member Functions" in the user's manual