DMX Decoder

[BobJ]

I use a couple of boxes that when addressed initiate some relays. But they require a DMX address for each relay (e.g. one for Red, One for Green and so on). I'm looking for a box or system (Raspberry Pi. Arduino perhaps) where I can Decode the data being sent to a single DMX address and have that presented to 8 pins for actuating my relay system. So, if I send "16" to that address then pin 4 will go high (or low). Are there any commercial units that would do this?

[david.elsbury]

Look up a “demux “

[timsabre]

Lots of boards available to do the whole thing including the relays. One example

https://www.amazon.co.uk/Switch-Dmx512-Controller-Output-Control/dp/B00S9KABRA/ref=asc_df_B00S9KABRA

 

Obviously arduino could do the 8 logic pins from DMX if you add a DMX shield but the DMX address has to be set in the code which may not be what you need

Edited January 15, 2020 by timsabre

[Brian]

Hmmm, a demux or normal relay board won't quite to what Bob wants. He wants to take a single byte from a DMX frame and use it to drive 8 relays: one relay per bit.

 

The old Milford 8-way relay board had a mode that would do that (IIRC).

[gyro_gearloose]

Seems like an odd request, given that 8 relays per byte gives you 4096 relays per universe! Controlling them will be a nightmare given that consoles more often than not work in percent rather than bits. It’s much easier to keep one relay per DMX address, and have them switch at 5, 50, or 95 percent. Perhaps the OP could explain why they want the type of system they are looking for? Edited January 15, 2020 by gyro_gearloose

[timsabre]

Hmmm, a demux or normal relay board won't quite to what Bob wants. He wants to take a single byte from a DMX frame and use it to drive 8 relays: one relay per bit.

 

The old Milford 8-way relay board had a mode that would do that (IIRC).

 

Ah yes, I didn't read his email carefully enough.

I very much doubt there will be any commercial unit to do this since it's an extremely non-standard thing to do, I assume the OP has some sort of custom control system on the other end that can control the bits independently.As Gyro says it would be much better to have 1 DMX address per relay, you're unlikely to run short of DMX addresses.

 

[sunray]

In the controls industry a lot of analogue signals are typically 0-10V or 4-20mA and relay boards of 2, 4 [example http://www.syxthsens...,-0-10v-input/] or to a lesser extent 6 relays are a common device. I have seen them used on a DMUX and exceptionally easy to set-up.

 

However the relays are operated on a binary decode of the analogue signal, ie relay 1 will have 8 off's and 8 on's as the channel is faded to full fader while relay 4 will have just 1. Additionally the 'stable' voltage [or current] for each state is quite small at something like 0.3V or 3% per step for a 4 relay module and 1% for 6 relays..

 

EDIT: 6RM's are more often operated in a 6 step mode [10% stable states}, either only ever 1 on or 1 on to 6 on, the later is handy for progressively switching on more boilers as more heat is required etc

Edited January 15, 2020 by sunray

[Brian]

Remembered correctly...

 

 

 

 

 

...like rocking horse ###### though. Although I do have some sitting waiting for 'that' project.

 

 

[E2A]

...like rocking horse ###### though.

 

 

How wrong could I be?

[alistermorton]

I was about to say that the whole Milford range had been acquired by a US company.

[musht]

ADJ did make a relay pack once but since dissapeared.

 

In UK QTX 4 and 12 channel DMX relays

 

https://cpc.farnell.com/qtx-light/154-111uk/DMX-relay-switch-pack-4-channel/dp/DP32807?st=qtx%20relay

 

Dinnae think Blue Point and Milford are related, there`s also Northlight

 

http://northlightdmx.com/DMXtoRelay.htm?fbclid=IwAR1xb_KYwaXnnNak9tnTqmADKHANWGJUvJzK1XEQrl0XPVxd6kfLGezb4ww

 

dunno if any allow byte wide addressing.

[Andrew C]

Again not quite what the OP seems to want, but XTBA are good for things DMX and weird.

 

 

[Brian]

Dinnae think Blue Point and Milford are related, there`s also Northlight

 

Maybe they are; maybe they aren't. The units are, however, functionally identical WRT the odd mode required by the OP.

 

Plus they are based in the US like the OP.

[alistermorton]

I'll echo your posting (credited to you, of course) on controlbooth, where he's also asked - might see it first there. Edited January 15, 2020 by alistermorton

[KevinE]

isn't this sort of thing likely to lead to potential stability issues? After all, there's no error correction. Does it have to be your actual DMX?

[musht]

Could always go pixel to relay, North American supplier ;-)

 

https://www.pixel2things.com/9-AC-Outputs-Fully-Assembled-p137348814

 

Not at all sure how the DMX stream is obtained as an output.