Is it possible to trigger reconfiguration of the Dual Configuration Altera FPGA IP Core on a MAX® 10 FPGA via the external nCONFIG pin? If so, will the config_sel setting set in the IP register be ...

As a result of our verification, reconfiguration can also be triggered by an external nCONFIG pin. 
Reconfiguration is triggered by the image specified by config_sel in the IP register.

(Reference: MAX 10 FPGA Configuration User Guide 
https://docs.altera.com/r/docs/683865/current/max-10-fpga-configuration-user-guide/max-10-fpga-configuration-overview

(Dual Configuration Altera FPGA IP Core Avalon -MM Address Map)

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Category: Programming / Configuration 
Tools: ^Quartus® Prime 
Device: ^MAX® 10