Multiple clamp modes in one AO

[rmo...@mit.edu]

Hi,

My lab has been using WaveSurfer 0.982 for a while now (see previous post). We have one BNC running from A0 to our External Command port on a Dagan BVC-700A, which can successfully run in both V clamp and I clamp when using WS's Test Pulse window (despite WS warning us that we cannot have two AO channels on the same terminal).

However, when trying to run a stimulation Sequence while recording, WS does not trigger a current or voltage injection as it does in the Test Pulse window, presumably because WS is internally preventing this from happening. Switching an AO channel to a different Terminal within the Devices & Channels dialog box allows us to stimulate while recording.

Given that we are limited by our hardware (our amplifier has only one EXT port), is there any way we can use the same terminal for two different channels? I'd be happy to make the necessary changes in the source code.

[rmo...@mit.edu]

After some thorough reading and testing of the source code, I've found the problem to lie within the Refiller, which the Test Pulse doesn't engage with. Going off the documentation, the refiller is needed to accurately time and buffer the output channels, and when it is initialized it must start all channels at the same time so they're ready in case a user wants to output current or voltage onto the same wsModel, whereas the Test Pulse "knows" for certain that only one channel will be used at a time.

I am no longer certain this would be an easy fix, but any pointers would be extremely beneficial. As it stands, we just have to change our AO channels to AO0 when doing test pulses, and separate them into AO0 and AO1 when starting to record, with the output of interest (current or voltage injection) in AO0.

Not sure if the developers (or any active/lurking members) still read this forum, but perhaps this could help someone in the future.

[David Nauen]

I think I've seen replies on this thread from Adam Taylor, the main developer, not that long ago...

David

---

From: waves...@googlegroups.com <waves...@googlegroups.com> on behalf of rmo...@mit.edu <rmo...@mit.edu>
Sent: Thursday, September 23, 2021 12:34 PM
To: WaveSurfer <waves...@googlegroups.com>
Subject: Re: Multiple clamp modes in one AO

 

--
You received this message because you are subscribed to the Google Groups "WaveSurfer" group.
To unsubscribe from this group and stop receiving emails from it, send an email to wavesurfer+...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/wavesurfer/742ecd7c-cb5b-4c2b-a2bf-a359d0360663n%40googlegroups.com.

[Adam Taylor]

Raul,

I realize this likely comes much to late to be helpful, but: What you're describing seems to work ok in the latest version of WaveSurfer, release 1.0.6.

FWIW,

Adam