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PostFri Feb 05, 2016 3:17 am

Hey BMD,

It would be mega-useful if you would publish the details of your GV100 implementation. Things like the address byte we need to send to find the mixer on multi-drop, the BAUD RATE (the original spec says between 300 and 76800), and given 76800 is a bit of a weird one, I suppose any speed could be used. Databits / Stopbits & Parity all seem to be fairly configurable on the original GV devices via dip switches, but I assume you've gone for a nice standard.

The effects byte, depending on how much of the ATEM properties you have chosen to expose this way might make for a good way of exposing Key Sources, and/or other properties. It occurs to me you have some lookup tables that map EX byte codes to the ATEM Properties.

The RS422 makes for a fantastic risk mitigation tool (addressing the possibility of network failure or temporary loss), even just being able to select cameras on preview and call CUTs means in the event of a network failure, an "emergency cuts panel" could be used to keep a mixer performing whilst network issues are addressed.

Any information you are able to share would be greatly appreciated.



Nicholas Gill

Blackmagic Design

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Re: GV100

PostFri Feb 05, 2016 4:20 am

Hi John,

Please find below ATEM GVG100 protocol integration details:

Serial port configuration: 38400, 8 data bits, 1 stop bit, odd parity.
Select Address: 0x30
ATEM acts as a GVG100 device

Effect Addresses:
0 is downstream key for some analogue controls
1 is Mix Effect 1
2 is Mix Effect 2

Please also find attached a complete function mapping.


GVG 100 Atem implementation.tiff
GVG 100 Atem implementation.tiff (855.81 KiB) Viewed 3011 times
Last edited by Nicholas Gill on Tue Apr 25, 2017 11:23 pm, edited 2 times in total.
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Re: GV100

PostFri Feb 05, 2016 8:18 pm

Many thanks Nick.

Gunnar Fernqvist

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Re: GV100

PostThu Feb 18, 2016 9:39 pm

Is it possible to use the GVG100 over ethernet as well? Or is it just for RS-422?


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  • Joined: Mon Apr 30, 2018 4:31 pm
  • Real Name: Mitchell Solomon

Re: GV100

PostTue May 01, 2018 8:27 pm

to control them ATEM via GV100 protocol over rs422
does one have to send the BREAK, then select address
then then GV100 command..

as in:

BREAK, 0x30,0x03,0x01,0xC1,0x02

select input #2 on program out using mix effect 01



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  • Joined: Sat Aug 10, 2019 10:38 am
  • Real Name: Wolfgang Kirmair

Re: GV100

PostSat Aug 10, 2019 10:40 am

Is it possible to set the input for an aux port via RS422?

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