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Using StageCaller's Heartbeat

Hey, all -

I just had a “doh!” moment when trying to help a user, and wanted to make sure everyone knew about this…

The current release of StageCaller offers a “Heartbeat” feature. It’s there in your settings. This is basically a pulse that you can set to send a tiny piece of data out from the device back to your show computer, to make sure the device is still ready and waiting to receive a cue. And, of course, I believe that, in both MIDI and OSC, that it’s good to keep the network a little bit active at all times - kind of like an RF pilot tone. (Please note that I have zero scientific basis for this belief, though when I’ve used the heartbeat, I’ve not had dropouts, so there is experimental evidence…)

“But,” you may be asking yourself, “how do I monitor this heartbeat?”

If you’re using MIDI, that MIDI pulse can be easily monitored using any MIDI monitoring tool or software. My tool of choice on the Mac is snoize’s aptly named, and totally free “MIDI Monitor” - you can download it here: http://www.snoize.com/MIDIMonitor/ I like this application because I’ve had it running in dozens of other (non StageCaller) settings, and it has never caused any problems, nor does it eat many resources.

On first launch, you do want to make sure no other MIDI software is running. After that, I think it can launch midstream.

When I use it, I set it to only remember the last few events; otherwise the screen fills up pretty fast, with a pulse every 3 or 5 seconds…

One of my colleagues has been playing around with an OSC monitoring tool, that’s till in a pre-beta state. I’m playing around with some other OSC monitors that already exist; I’ll post an announcement if either of these work out. But, please note - you can certainly use OSC to trigger your device, and MIDI for the Heartbeat - you just need to make sure you have a MIDI session running.

Hope this is of use!


Hello, I just started trying out StageCaller - about to do a show with a lot of phone ringing. Very cool app!

I’m working on a heartbeat monitor in Max. Simple red Light/green Light indicator. I have to work on the interface more to make it friendly to use with the Max Runtime app (free, but doesn’t allow patch editing, i.e. have to make the IP address of the phone easily configurable, etc.) The useful thing about it is that it regularly trips the disconnected status if it doesn’t receive the heartbeat. which I worried wouldn’t be as apparent on a traditional monitor. I’m focusing on OSC at the moment. Max 6.1.9 with OSC-Route for free from U of C Berkeley.

I modified the Heartbeat OSC string in StageCaller to include the time interval: OSC:/heartbeat/30 automatically sets the time interval in the Max patch to 30. Not sure if this would be valuable to other apps, but if StageCaller could optionally append the heartbeat string with the interval, then it would only ever have to be set in one place. Again, I’m only working on an OSC monitor at the moment, but It would be cool if when using MIDI, a CC number could be set for the heartbeat and its value could be the time interval.

I was also wondering if it would be possible to also have StageCaller send a Arm/Disarm status via OSC (or MIDI) to the same destination as the heartbeat whenever that status changes. I added functionality to the Max patch to arm and disarm StageCaller, but it’s always nice to be able to get feedback.

I’ve also observed that while interacting with StageCaller (iPhone 5s, iOS 8.3 & 8.4), the heartbeat doesn’t transmit on schedule. While set to a 30 sec interval, I noticed the heartbeat coming in between 50 and 60 seconds while editing/viewing settings or actions. StageCaller never lost contact - I confirmed by arming and disarming or firing a cue. Not a big deal, but good to know. I’ve allowed a 40% margin of error in delay as the regular heartbeat fluctuates at +/- 20% (or Max’s timer is fluctuating. Or both…)

Thanks again for the App and if anyone has any thoughts on what could be useful for the heartbeat monitor, let me know. I’ll try to get a better working patch up for folks to try out soon.

Over the last hour or so, I’ve had QLab 3 (OS X.8.5), Max 6.1.9 and StageCaller running with no problems in communication with StageCaller.