# Voltage from port DAC0 **URL:** \ **Category:** Support\ **Tags:** unsolved-mystery\ **Created:** [August 12, 2021, 5:51pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98 "2021-08-12T17:51:47Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 1, 2021, 6:36pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/21 "2021-10-01T18:36:04Z")
> Btw- does this new plug-in fix both of the issues that we’ve been having (the high DAC0 output on some Labjacks and the lack of modulated DAC0 output with the most recent plugin)? I only saw the first issue with my U6, and that’s what I fixed. It’s possible the other issue is related and the new plugin will fix it, too, but I don’t know. Chris ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 1, 2021, 7:07pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/22 "2021-10-01T19:07:53Z")
Hi Chris, The new plugin doesn’t work- I get the “no factory for object type” error. Lindsey. ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 1, 2021, 7:30pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/23 "2021-10-01T19:30:15Z")
Huh. I just tried using the plugin on my work Mac (built it on my home Mac). When I launch MWServer, I get a pop-up window saying, “LabJackU6Plugin.bundle can’t be opened because Apple cannot check it for malicious software.” I’m not sure why that’s happening. I was able to work around the issue by going to System Preferences → Security & Privacy → General and clicking “Allow Anyway” next to the message saying the plugin was blocked (see attached image). After doing that and re-launching MWServer, the plugin loaded correctly. Did you get that error message, too? If so, can you try manually allowing the plugin as I described? If that doesn’t work, I’ll push my fix to GitHub so you can build the plugin yourself. I won’t be able to do that today, though, since that code is on my home Mac. Chris ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 1, 2021, 7:30pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/24 "2021-10-01T19:30:15Z")
Attachment: [allow\_plugin.jpg](https://mworks.discourse.group/uploads/short-url/uegJDgPhYjgPcnHi2AkOdBoaf6l.jpeg) (172 KB) ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 1, 2021, 7:33pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/25 "2021-10-01T19:33:09Z")
No- that is not the issue. I am able to launch both the Server and Client, and connect. It is only when I load an experiment that I get the error. It is definitely the new plugin since I can swap back to the previous plugin and load the experiment. Lindsey. ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 1, 2021, 7:39pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/26 "2021-10-01T19:39:00Z")
OK. Can you run the following command in Terminal and send me the output? If MWServer is running, please close it first, as this command will open it again: ```auto MWORKS_WRITE_MESSAGES_TO_STDERR=1 /Applications/MWServer.app/Contents/MacOS/MWServer ``` If the LabJack plugin is failing to load, there should be some error messages about that in the output. Thanks, Chris ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 1, 2021, 8:09pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/27 "2021-10-01T20:09:31Z")
Hi Chris, I think there was an error with the unzipping- it now loads. And it does resolve the DAC0 high issue. However, there is still no modulation of DAC0 output with this plugin (I tried using a labjack from a different rig that had normal DAC0 output this morning, and there’s nothing). I think you should have a copy of my experiment that you could try. Would you take a look to see if you’re getting appropriate DAC0 output? Thanks, Lindsey. ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 1, 2021, 8:22pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/28 "2021-10-01T20:22:52Z")
OK, thanks for the update. I can do some more testing on Monday. Should I use the experiment attached to [this comment](https://mworks.tenderapp.com/discussions/problems/528#comment_49298429) (Glickfeld\_2AFC\_Experiment.zip)? Chris ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 1, 2021, 8:34pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/29 "2021-10-01T20:34:47Z")
Yes- that’s the correct experiment. And this variable set should set DAC0 high when the stimulus goes on. Thanks, Lindsey. ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 1, 2021, 8:34pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/30 "2021-10-01T20:34:47Z")
Attachment: [test\_human.xml](https://mworks.discourse.group/uploads/short-url/4ZBPPu1V5O73eSdxL6KDx51r9qm.xml) (14.4 KB) ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 4, 2021, 3:46pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/31 "2021-10-04T15:46:19Z")
Hi Lindsey, Using the latest plugin code, the DAC output definitely works for me. I have an LED connected to DAC0 on my U6. When I set the variable `tTrialLaserPowerMw` to a non-zero value, the LED goes on. If I set it back to zero, it turns off. To confirm that your device does the same, try running the attached experiment, which just toggles `tTrialLaserPowerMw` between 10 and zero every second. The problem with your experiment is that it never sets `tTrialLaserPowerMw` to anything but zero. It looks like the variable `trialLaserPowerMw` is meant to determine the “on” state power for the laser. However, both the experiment code and the variable set you sent me set this variable to zero. If I set `trialLaserPowerMw` to 10, then I see my LED periodically go on and off, just as it does in the demo experiment. (There’s also a `block2TrialLaserPowerMw` variable, which is also assigned to `trialLaserPowerMw` under some conditions and is set to 3 in your variable set. However, it’s not clear it was ever used in my test runs.) As for why your experiment code works correctly with an older version of the plugin, my best guess is that some code change (by someone on your end, not by me) altered the behavior of the plugin with respect to DAC output. I see that GitHub user ziyeye has [made a number of changes](https://github.com/Glickfeld-And-Hull-Laboratories/LabJackU6_Plug-in/commits?author=ziyeye), some of which definitely touch on the DAC control bits. Do you know what version of the code the “old” plugin was built from? I’m guessing it predates some of these changes. Cheers, Chris ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 4, 2021, 3:46pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/32 "2021-10-04T15:46:19Z")
Attachment: [dac\_cycle.mwel.zip](https://mworks.discourse.group/uploads/short-url/pGWUNNCdBllUyoTR20U6ObN7hVM.zip) (524 Bytes) ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 4, 2021, 3:55pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/33 "2021-10-04T15:55:40Z")
Hi Chris, Thanks for checking this, we will give your reduced code a try. However, I’m confused that tTrialLaserPowerMw is always zero. It gets set on line 1553 of that code, if tTrialLaserPowerMw\_trigger is greater than 0, which it should be on line 1349 for “block2” trials (which all trials are in the experiment that I sent you). Yes- Ziye had made changes to our plugin to use DAC0 to drive LED/laser output ~five years ago. This is one of the ways that our plugin currently diverges from Mark’s. However, I don’t know what “base” she used for those changes- and I had assumed that all changes you’d been sending us were off of her base. And I’m not sure how to hunt these origins down. Lindsey. ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 4, 2021, 3:56pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/34 "2021-10-04T15:56:41Z")
> As for why your experiment code works correctly with an older version of the plugin, my best guess is that some code change (by someone on your end, not by me) altered the behavior of the plugin with respect to DAC output. Oh, wait – you said that reverting to an older plugin _didn’t_ restore DAC0 output, right? Never mind, then, and apologies to ziyeye! Chris ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 4, 2021, 3:58pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/35 "2021-10-04T15:58:54Z")
Yes- that’s correct. Reverting to the previous build of the plugin didn’t enable DAC0 output. ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 4, 2021, 4:06pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/36 "2021-10-04T16:06:33Z")
> However, I’m confused that tTrialLaserPowerMw is always zero. It gets set on line 1553 of that code, if tTrialLaserPowerMw\_trigger is greater than 0, which it should be on line 1349 for “block2” trials (which all trials are in the experiment that I sent you). In the version I have, `tTrialLaserPowerMw_trigger` is set to the value of either `trialLaserPowerMw` or `block2TrialLaserPowerMw`. As I said, I don’t know if `block2TrialLaserPowerMw` was ever used in my test, but `trialLaserPowerMw` was definitely always zero. Manually making it non-zero caused my LED to go on. Chris ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 4, 2021, 4:17pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/37 "2021-10-04T16:17:46Z")
Yes, in the variable set I sent you, trialLaserPowerMw is 0, but block2TrialLaserPowerMw is set to 3. It’s set so that 100% of trials are block2 so it should use the block2TrialLaserPowerMw. Do you see tBlock2TrialNumber getting set to 1 on each trial? ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 4, 2021, 4:22pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/38 "2021-10-04T16:22:51Z")
> Do you see tBlock2TrialNumber getting set to 1 on each trial? No, it’s always zero. ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 4, 2021, 4:29pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/39 "2021-10-04T16:29:35Z")
That’s very strange. doBlock2 and doBlock2SeparateOdds are both set to 1? And block2TrPer80Level1 = 80? I’ll make sure that tBlock2TrialNumber is being set on our end… Lindsey. ---
**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\ **Post date:** [October 4, 2021, 5:34pm UTC](https://mworks.discourse.group/t/voltage-from-port-dac0/98/40 "2021-10-04T17:34:19Z")
> doBlock2 and doBlock2SeparateOdds are both set to 1? And block2TrPer80Level1 = 80? Yes to all. [Previous page](https://mworks.discourse.group/t/voltage-from-port-dac0/98.md?page=1) [Next page](https://mworks.discourse.group/t/voltage-from-port-dac0/98.md?page=3)