Why can’t I access the Intel® MAX® 10 device via JTAG when the TDO pin is used as a user input pin in user mode?

Description

Due to a known problem in the Intel® Quartus® Prime Software, when the JTAGEN pin option is enabled for Intel® MAX® 10 devices, the JTAG TDO pin does not work in hardware when it is assigned as an input pin in user mode even if the JTAGEN pin is pulled high in user mode. 

The JTAG TDO pin works only when assigned as bidirectional or output pin in user mode.

 

 

 

 

Resolution

This problem is scheduled to be fixed in a future version of the Intel Quartus Prime Software.