I'm using ModelSim Altera Starter Edition 6.6 for simulating some very simple designs. I started a new project, compiled and everything was ok. But when I had wanted to start simulation, I have opened the wave window and all I get is:# Invalid time string specified: and the wave window is just a big grey window. Even an other project that I had already simulated stopped working. I tried deleting some configuration files and nothing. I reinstalled the whole software and still nothing. Searching on google and on the forums I even found some threads of people with similar problems, but none got a solution. And I wanted also to ask why Altera changed the simulator integrated in Quartus II 9.1 for ModelSim. I used the 9.1 version for a while and it was so much easier to simulate. What does ModelSim offer that Quartus couldn't handle? Thanks, Daniel K. Franch

--- Quote Start --- # Invalid time string specified --- Quote End --- If you are simulating Verilog, then try adding '-t ps' to the vsim command line to set the timescale to 1ps. You might also want to add something like `timescale 1 ps / 1 ps to your Verilog. --- Quote Start --- What does ModelSim offer that Quartus couldn't handle? --- Quote End --- A programmable method of generating a testbench. Drawing stimulus waveforms works for only the simplest of testbenches. Cheers, Dave

you should also get more stimulus reuse when using HDL/C/etc test benches

Actually, I'm simulating VHDL. I tried adding -t ps to the command line, but it didn't work. It still gives me that message and a grey window when I try to open the wave window. I guess as I am testing very simple projects, ModelSim seems over-complicated to me. But I probably should learn how to use it know, for it will be easier when I try to simulate more complex projects.

--- Quote Start --- I'm simulating VHDL. --- Quote End --- Post your code. --- Quote Start --- I guess as I am testing very simple projects, ModelSim seems over-complicated to me. But I probably should learn how to use it know, for it will be easier when I try to simulate more complex projects. --- Quote End --- Its worth learning. There's an example at this thread you can use: http://www.alteraforum.com/forum/showthread.php?t=32386 Cheers, Dave

My code is the following: entity ex_or is port(a,b,c,d : in bit; x,y,z : out bit); end ex_or; architecture a of ex_or is begin x <= a xor b; y <= a xor b xor c xor d; z <= (a and b) xor (c and d); end a; It is just an exercise from a Digital Electronic book, from the chapter of XOR gates. I'm just trying to get used with VHDL. I already simulated an equally simple code to test AND and OR gates and it worked yesterday. But when I try to do it now, I get the same result. I will take a look in this example, it seems useful. Thanks. --- Edit: I just tried the example and got the same thing: Invalid time string specified, grey wave window. It doesn't seem to be something with code, but in some configuration or command.

# Invalid time string specified: in ModelSim

18 Replies

Altera_Forum
Honored Contributor
14 years ago
--- Quote Start ---
Sounds like it.

When you get a grey wave window, do you get the time string error?

--- Quote End ---

Yes. They both come always together. And show up when I go on View>Wave.
Altera_Forum
Honored Contributor
14 years ago
Look at the sim.tcl script, and implement each step manually. eg., vcom, then vsim, and then type 'add wave *' to add all the waveforms to the wave window.

Does that work?

Cheers,
Dave
Altera_Forum
Honored Contributor
14 years ago
I wen through sim.tcl step by step. All worked fine, until I the vsim command. It instantly opens the wave window and I get that same old error. I try to close the window and start typing the commands on example_tb.do but on the first one (quietly WaveActivateNextPane {} 0) it tries to open wave window again and I get the error once more.

Is this a problem with vsim?

---

Edit: I tried closing the wave window everytime it appeared after a command, but that doesn't seem to help. I can't see anything this way. It seems to be something specific to the wave window.
Altera_Forum
Honored Contributor
14 years ago
--- Quote Start ---
I wen through sim.tcl step by step. All worked fine, until I the vsim command. It instantly opens the wave window

--- Quote End ---

I've never seen the wave window open up when using the vsim command. Perhaps there is come configuration file that has been screwed up - is there a modelsim.ini file in your local directory? Delete it.

--- Quote Start ---

I try to close the window and start typing the commands on example_tb.do but on the first one (quietly WaveActivateNextPane {} 0) it tries to open wave window again and I get the error once more.

--- Quote End ---

Look at the script again, the procedure example_tb just runs a couple of commands, i.e., essentially

vsim -novopt -gWIDTH=$WIDTH example_tb do scripts/example_tb.do run -a

You don't type in the contents of the example_tb.do file, you just source it, and it will open the wave window.

Take a screen shot of what you are seeing and post it.

Cheers,
Dave
Altera_Forum
Honored Contributor
14 years ago
Wave window shouldn't appear automatically? Awkward. It does. This way:
http://img252.imageshack.us/img252/1697/invalidtimestringspecif.png

I tried just sourcing example_tb.do also, but got the same result.

I searched for a modelsim.ini but I haven't found it. I will try looking for something like that on the ModelSim folder.

---
Edit: I am now on my Linux partition. I will try installing Quartus and ModelSim here to see what I get.
Altera_Forum
Honored Contributor
14 years ago
Well... I tried installing ModelSim in my Linux partition but that was even worse. I couldn't even run it. I guess that's because I'm running on a 64-bit processor and ModelSim doesn't have a 64-bit version for Linux.
So I tried uninstalling everything related to Altera in Windows, and then reinstalling Quartus II and ModelSim, everything updated to the last version.

And I still get the same thing. I have absolutely no idea about what's going on. I'm just trying to get a hang on the basics of FPGAs and VHDL and the tools associated with them, but I'm getting a real bad headache with ModelSim. I'm kind of losing hope about using it. What is a good substitute for it (I guess there is some alternative to it)?

---

Edit: oh, I found the modelsim.ini in my folder, but that didn't change anything too.
Altera_Forum
Honored Contributor
14 years ago
--- Quote Start ---
I'm getting a real bad headache with ModelSim. I'm kind of losing hope about using it.
--- Quote End ---
I've never had a problem with Modelsim under Linux or Windows.

How about this;

1) Download and install VirtualBox

2) Download and install Ubuntu 11.10 VirtualBox. I prefer the older Gnome interface, so follow this:

http://www.virtualhelp.me/linux/470-install-gnome-in-ubuntu-1110-oneiric-ocelot

3) Install Quartus and then Modelsim Altera-Starter-Edition

Just to be on the safe side, start with a 32-bit OS and 32-bit versions of the tools.

Cheers,
Dave
Altera_Forum
Honored Contributor
9 years ago
I got the same error with version 10.c. Deleting the Registry did not work for me. But I could solve it by going to the GUI, Simulate>start Simulation, and changing the resolution to anything other than "default". Then restart ModelSim and it should work.

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# Invalid time string specified: in ModelSim

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