how can i determine which devices are used at the moment?

[billko]

I can see all kinds of issues with this.  Human issues.  It's probably better so send an email or IM to your colleagues saying you're going to be using the equipment.

[Dennis_Knutson]

Hi Gerd,

Okay, I see what you were getting at. Your approach seems the most reasonable.

[JÞB · Accepted solution]

Use VISA Lock Async.

Your main program can periodically poll the resource lock state and disable the locked VISA Resources.  Make sure you keep a list of "MyLocks" so you don't disable control of instruments that specific bench is using.

[Dennis_Knutson]

Jeff,

I don't think the lock works across different computers.

[rolfk]

It won't.

Maybe if you setup remote VISA and share the resources through that, but that is really just complicating the setup even more (albeit might allow to get rid of the LAN extender).

[JÞB]

---

@Dennis_Knutson wrote:
Jeff,

I don't think the lock works across different computers.

---

Right of course-  But updating a NPSV with Lock Status is fairly straight forward

[omer32]

Hi again all,

Jeff, can you explain a little more?

[JÞB]

NPSV= Network Published Shared Variable

All of your "User" Systems should be able to write and read to a "Master" location to share information about the usage of the shared devices.

e.g.

• User A looks for availability of devices it wants by reading the "Lock" or "Checkout" status of the desired devices
• User A checks out those devices it whants to reserve
• Begin using reserved devices

If user B wants those devices the NPSV will let them know it is in use already (Hopefully with some additional info like, the name of User A)

• User B can tap on the cube wall of User A and negotiate whos experiment is more important
• User A doesn't really need the data so he releases the locks and User B sees that the devices are available again.

-Rinse-Repeat

[billko]

---

@JÞB wrote:

NPSV= Network Published Shared Variable

All of your "User" Systems should be able to write and read to a "Master" location to share information about the usage of the shared devices.

e.g.

• User A looks for availability of devices it wants by reading the "Lock" or "Checkout" status of the desired devices
• User A checks out those devices it whants to reserve
• Begin using reserved devices

If user B wants those devices the NPSV will let them know it is in use already (Hopefully with some additional info like, the name of User A)

• User B can tap on the cube wall of User A and negotiate whos experiment is more important
• User A doesn't really need the data so he releases the locks and User B sees that the devices are available again.

-Rinse-Repeat

---

That's kind of why I suggested it be handled by humans.  A schedule might help so that you know when the equipment will be available.  (Because you signed up for a time slot.)

Of course this doesn't work well if each person just needs it for a few minutes at a time.