What is a CRMX linking key and do I need CRMX² to use it ?
CRMX linking key is an 8 digit code that makes pairing, pre-lighting and working with different crews a breeze. So far we used to manually link fixtures by setting them into the unlinked state (resetting/unlinking them) and clicking the Link button on the CRMX transmitter. This is really easy to do, especially if you have a single universe and a small amount of fixtures. However when you start having more than a couple dozen fixtures and a handful of universe it turns into an unwanted ballet of resetting, relinking and now I need an ibuprofen …
Linking key solves this issue by setting up both the CRMX transmitter and the CRMX receivers with a key that makes them instantly paired. This is great if you run a studio with overhead fixtures that you don’t want to get to every time you have a new team coming in, or if you have a pre-lighting team, they could do all of the pairing and you could take over with your own DMX kit effortlessly.
Unlike popular belief, linking key does not depend on the CRMX² update, it’s a different thing that works both with CRMX Classic and CRMX², for more info about the difference, check out our CRMX article (coming soon).
What’s the deal with the Stardust Linking Key ?
However linking key is implemented in two different ways, one is the LumenRadio Stardust that uses a single linking key for the whole unit, whether it is configured in 4 universe CRMX Classic mode or in 8 universe CRMX² mode, you have to choose one linking key for the whole unit and then manually select the output from A through H on your receiver. The other which is the most common way covers all the CRMX classic transmitters out there, including but not limited to FTS Cerise, TimoTwo enabled devices, Moonlite, Aputure Sidus, Ratpac Satellite … This mode uses a single unique linking key per universe, this means for each key the only usable universe is A.
This is a limitation chosen by LumenRadio, there is no way to have multiple linking keys on the Stardust and there is no way to have a single linking key with multiple universes on anything else.
Another added confusion is that fixtures will let you select an output even if you’re not connected to a Stardust, however only the output A will actually work if using something like Cerise.
Another confusion is that a transmitter with multiple TimoTwo chips inside like Cerise needs a different key for each output, setting the same linking key on more than one output leads to the outputs trying to send data to the same receivers, causing bugs, glitches, flashes …
Can I use Linking Key with a fixture that doesn’t expressly supports it like a DMG DASH or a generic CRMX receiver ?
Yes, there’s an easy trick to do so.
As the manual CRMX linking process (pressing the link button) acts like sending the key to the receivers, we can set the key beforehand in the transmitter and then manually link our fixtures or receivers, then our fixtures/receivers will just memorize said linking key until they are manually unliked/reset.
What’s the deal about the CRMX transmitter cloning ?
An interesting but experimental use case of the linking key is that you could technically have two transmitters using the same linking key, if they are close to one another this is absolutely useless and will cause issues as explained previously. However if you have a subject might move in and out of range (such as a car chase or an actor with a prop on a large set), you could put transmitters at regular intervals so that your receiver would always be in the range of one of the transmitters and jump smoothly to the next in range.
How can I set a linking key when using Cerise CRMX Transmitter ?
Just head to the Cerise WebUI, and click on the linking key button (it’s the one next to the link and unlink buttons) corresponding to the output you wish to set a linking key on. Then type in the 8 digit ley and press “Confirm”. This will reset any already linked receivers, and they will need to be relinked. You must set different linking keys for each output if you have a 2U or 4U. On the receiver side make sure you’re using output A or 1 for each different linking key.
If you don’t see the linking key make sure both Cerise is up to date, as well as the TimoTwo modules.
