LTSpice won't let me change stop time of transient analysis  - Page 1
Forum section: electronics / beginners

author: MathWizard
author_rank: Super Contributor
timestamp: September 11, 2022, 07:05:58 pm
content: I've been using LTSpice for a few years now, and this happens fairly often to me in LTSpice when I have a .tran xx statement, like now .tran 40, and I tried nearly ten times to change it to .tran 80 , by right clicking on it and changing 4 to 8 in either the top box, or the bottom box. Then clicking OK, or just hitting enter.And it never worked, it's still .tran 40I exited the program, and tried it again 2-3 times, same problem. Then I Rclicked it, hit cancel on the analysis window, which brings up the statement or .op text box, and there I set 80, and it worked.Anyone else suffer that problem too sometimes ? I remember having it years ago, and on Linux too, and I keep it up to date.

author: mikerj
author_rank: Super Contributor
timestamp: September 11, 2022, 09:23:19 pm
content: So you can change the value in the dialog but after clicking "OK" the value in the schematic doesn't get updated? Do you see the same issue with other dot commands like .param, .include, .step etc?What happens if you try undo/redo after (unsuccessfully) changing the value, does the schematic update?

author: MrAl
author_rank: Super Contributor
timestamp: September 12, 2022, 10:43:09 am
content: Quote from: MathWizard on September 11, 2022, 07:05:58 pmNever once but maybe you can check that the simulation was done or just paused.

author: Dave
author_rank: Super Contributor
timestamp: September 12, 2022, 01:43:43 pm
content: This is a fairly old LTspice bug that has persisted ever since the introduction of LTspice XVII.As far as I'm aware, the whole LTspice development is a 1 man project. I'm guessing Mike simply doesn't have an idea where the problem might lie and therefore it hasn't been fixed in all this time (6 years now?).There is a workaround, though. When you right click on a SPICE directive and open the dialog where you modify those values, you need to click Cancel. It will then pop up with a new dialog where you have just the raw text of that directive. Modify that, click okay and it should work.

author: Ian.M
author_rank: Super Contributor
timestamp: September 12, 2022, 02:16:26 pm
content: I've never seen it running LTspice XVII on Windows 7 or 10. Is it WINE specific, or have I just been very lucky?

author: tooki
author_rank: Super Contributor
timestamp: September 12, 2022, 04:42:07 pm
content: Quote from: Dave on September 12, 2022, 01:43:43 pmAnd given that he left ADI a while ago (a few years ago IIRC), he’s certainly not going to fix it now. (On the bright side, if/when ADI does assign another developer to LTspice, maybe we’ll get someone who doesn’t have such a user-hostile attitude, so that the Mac version can get a more… sane user interface.)

author: Dave
author_rank: Super Contributor
timestamp: September 12, 2022, 05:33:55 pm
content: Just looked him up. He apparently left the company in 2020 and started his own. He's working on a new simulator called SPQR now.Imagine the revolution if ADI open sourced the software.Even if they kept the proprietary secret sauce simulation stuff (and model encryption) hidden in a pre-compiled static library, and just released the GUI part of the code, the progress would likely be tremendous.One can dream...

author: MrAl
author_rank: Super Contributor
timestamp: September 12, 2022, 11:25:14 pm
content: Quote from: Ian.M on September 12, 2022, 02:16:26 pmYeah that's interesting too i've never seen that happen once in all the times i used LT Spice, except if the simulation is still running and you dont realize it, then you have to stop the simulation and then you can edit anything. This always worked for me never once did it happen any other way. This must mean it is operating system specific.

author: MathWizard
author_rank: Super Contributor
timestamp: September 13, 2022, 02:01:13 am
content: Well it's no big deal, usually it only happens once, and it's not all the time. And the numbers will change in the boxes, but after I click ok/hit enter, the .tran doesn't change.I think it's more Edit-Sim-Cmd box related than, say a .op statement in general.Also in the EditSim box, IDK if it's a bug, but if I run an AC analysis, then open the Editsim box and choose to run a trans. analysis, it will auto copy the AC fields, into the trans. fields, and vice versa, etc, which never helps.

author: iMo
author_rank: Super Contributor
timestamp: September 13, 2022, 10:29:46 am
content: I see it sometimes here as well (latest LTspice, Win10) when I press Enter while changing something there. I learned I have to click OK, then it works always here.