Why is the "Enable input tri-state on active configuration pins in user mode" option disabled in the Quartus® II software version 10.0?

Description

Due to a problem in the Quartus® II software version 10.0, the Enable input tri-state on active configuration pins in user mode option on the Configuration panel of the Device and Pin Options dialog box is disabled for Cyclone® III, Cyclone® III LS, Cyclone® IV E, Stratix® III, and Stratix® IV devices.

Resolution

To work around this problem, you can enable this option by adding the following assignment to your Quartus II Settings File (.qsf):

set_global_assignment -name TRI_STATE_SPI_PINS ON

This problem is scheduled to be fixed in a future release of the Quartus II software.

Related Articles

• How do I assign dual-purpose pins to be a user I/O after configuration in Quartus II software version 10.0?