2.1. I/O Planning Overview 2.2. Assigning I/O Pins 2.3. Importing and Exporting I/O Pin Assignments 2.4. Validating Pin Assignments 2.5. Verifying I/O Timing 2.6. Viewing Routing and Timing Delays 2.7. Analyzing Simultaneous Switching Noise 2.8. Scripting API 2.9. Managing Device I/O Pins Revision History
2.4.2. Checking I/O Pin Assignments in Real-Time
Live I/O check validates I/O assignments against basic I/O buffer rules in real time. The Pin Planner immediately reports warnings or errors about assignments as you enter them. The Live I/O Check Status window displays the total number of errors and warnings. Use this analysis to quickly correct basic errors before proceeding. Run full I/O assignment analysis when you are ready to validate pin assignments against the complete set of I/O system rules.
Note: Live I/O check is supported only for Arria® II, Cyclone® IV, MAX® II, and Stratix® IV device families.
Live I/O check validates against the following basic I/O buffer rules:
- VCCIO and VREF voltage compatibility rules
- Electromigration (current density) rules
- Simultaneous Switching Output (SSO) rules
- I/O property compatibility rules, such as drive strength compatibility, I/O standard compatibility, PCI_IO clamp diode compatibility, and I/O direction compatibility
- Illegal location assignments:
- An I/O bank or VREF group with no available pins
- The negative pin of a differential pair if the positive pin of the differential pair is assigned with a node name with a differential I/O standard
- Pin locations that do not support the I/O standard assigned to the selected node name
- For HSTL- and SSTL-type I/O standards, VREF groups of a different VREF voltage than the selected node name.