Page 1 of 1

Multiple DMX USB's only working in the same mode - 'Open RX' or 'Open TX' mode

Posted: Tue Sep 03, 2024 5:27 pm
by theMenace
Hi all
I have an issue when using two simple DMX USB devices (specifically this 'FT232R USB UART' https://www.aliexpress.com/item/1005004 ... 1802taehwe ).
They both work flawlessly when used independently, whether this is output or input.
However, I want to use one as input(connecting an external controller) and another as output(connecting to lights).

The issue is that when I change the mode for one device, the other changes with it, even though the two devices are individually recognized.

Is this just a limitation of the driver and simple hardware or am I just not seeing my mistake?

I have attached a link to an image of the configuration window where I would want to set one to 'open RX' and the other to 'OpenTX'.

https://ibb.co/857HVzq

Thank you in advance

Re: Multiple DMX USB's only working in the same mode - 'Open RX' or 'Open TX' mode

Posted: Wed Sep 04, 2024 7:19 am
by mcallegari
Do they have the same serial number??
That sounds like the real issue...

Re: Multiple DMX USB's only working in the same mode - 'Open RX' or 'Open TX' mode

Posted: Wed Sep 04, 2024 9:04 am
by theMenace
Hmm good point.
I had not seen that.

I have researched the issue with the serial number:
I tried reprogramming the FTDI ft232rl with a new serial number with the FT_PROG software from FTDI, but without any luck.
I have found that these cheap/fake FTDI ft232rl chips all come with the same serial number, namely A50285BI.
Even worse is that the fake chips do not have any reprogrammable EEPROM making it impossible to change the serial number ( I think, please prove me wrong).

However, I will need to get another chip to see if the serial number issue is actually what is causing the original issue.

Re: Multiple DMX USB's only working in the same mode - 'Open RX' or 'Open TX' mode

Posted: Wed Sep 04, 2024 1:53 pm
by GGGss
When they 'share' the same serial, QLC+ can't distinguish one from the other...
(When they 'share' the same serial, it is a fraudulent copy of an existing one ...)