FPGA Q&A: ModelSim Simulation Errors

quartus II 15.0 中解决仿真报错 Error: (vsim-19) Failed to access library 的问题_quartus ii输入程序时failed-CSDN博客

文章浏览阅读3.2w次，点赞22次，收藏79次。初次使用Quartus II 15.0，简单的画好器件连接图后新建VWF文件进行仿真，此处使用的仿真软件是modelsim，发现在进行功能仿真（run function simulation）时出现报错如下：Error: (vsim-19) Failed to access library "cyclone_ver" at "cyclone_ver"这样类型的报错，有96处，大致意思为_quartus ii输入程序时failed

https://blog.csdn.net/u013753393/article/details/50350138

1. Command: vsim -L altera_primitives -L altera_mf -L 220model work.top_tb

• This command runs the simulation for the testbench top_tb located in the work library.

• The L options specify additional libraries that ModelSim needs to use during the simulation. In this case:
• altera_primitives: Altera primitive library
• altera_mf: Altera Megafunction library
• 220model: Altera model library

• ModelSim applies optimization techniques by default to improve simulation performance. This optimization may remove or hide some signals that it deems unnecessary for simulation output, leading to certain signals not being visible in the wave window.

• Signals not directly affecting outputs or used in assertions might not be visible.

2. Command: vsim -voptargs=+acc -L altera_primitives -L altera_mf -L 220model work.top_tb

• Similar to the first command, this runs the simulation for top_tb using the specified libraries.

• voptargs=+acc: This additional flag modifies the optimization settings of the simulation.

• +acc (Access): This flag tells ModelSim to keep all hierarchical signals and variables visible by providing full access (acc) to all objects within the design.

• By using voptargs=+acc, you effectively disable certain optimizations that would otherwise hide internal signals. This makes all internal signals and variables visible and accessible during simulation, allowing you to add them to the wave window.

• This setting is particularly useful for debugging purposes as it ensures no signal is optimized away, providing a comprehensive view of all signals in the simulation.

Conclusion:

• vsim -L altera_primitives -L altera_mf -L 220model work.top_tb:
• This command runs the simulation with default optimizations enabled. It is suitable for final simulations or when simulation performance is a priority.
• Some signals may not be visible in the wave window due to optimizations.

• vsim -voptargs=+acc -L altera_primitives -L altera_mf -L 220model work.top_tb:
• This command runs the simulation with optimizations that preserve all signals (+acc). It is ideal for debugging, as it provides complete visibility of all signals and variables in the design.
• It disables certain optimizations that might hide signals, making it easier to debug but potentially slower in simulation performance due to the increased amount of data being processed.