Simultaneous foot presses in IO mode

[Edsko de Vries]

Hi,

I recently received my EurekaPROM 3.2 and just installed it into the FCB1010. I am planning to use the chip in IO mode, going to design an Ableton Max for Live device for it, as well as write a Linux utility that allows me to control various things (the latter not music related, just for fun). Installation was easy enough (no hot glue needed to be removed, yay), and it booted into the 3.2 EurokaPROM no problems.

I had purchased the EurekaPROM specifically because I found that with the FCB1010 as delivered by Behringer it's impossible to use the foot switches simultaneously; once you press and hold switch 1, switch 2 is not responsive. This precludes quite a few musical applications (imagine holding switch 1 as a piano sustain pedal for example, and using switch 2 to trigger something). After some googling I found a post on the FCB1010.eu forums (https://fcb1010.groups.io/g/main/topic/76066023) that seemed to suggest that with the EurekaPROM in IO mode simultaneous switches like this should be possible.

Unfortunately, that does not quite seem to be the case. Some examples:

1. Here is the output of aseqdump when I press switch 1, then press switch 5, then release switch 1, and finally release switch 5:

 28:0   Control change          0, controller 104, value 1
 28:0   Control change          0, controller 104, value 5

<nothing>
 28:0   Control change          0, controller 105, value 5

The release of switch 1 is never sent. 

2. More strangely, when I reverse the order, press 5, press 1, release 5, release 1, I get

 28:0   Control change          0, controller 104, value 5

<nothing>
 28:0   Control change          0, controller 104, value 1
 28:0   Control change          0, controller 105, value 1

When I press switch 1 (while holding 5), no message is received at all. Then when I release switch 5, only then do I get the press of switch 1 (but no message of the release of 5). The final message of the release of switch 1 is as expected.

3. If I press 1, press 5, release 5, and then release 1, I get

 28:0   Control change          0, controller 104, value 1
 28:0   Control change          0, controller 104, value 5
 28:0   Control change          0, controller 104, value 1
 28:0   Control change          0, controller 105, value 1

When I release switch 5, I'm instead getting a spurious message indicating another press of 1, and then when I release switch 1, I'm getting (unexpected) the release for 1. 

4. Finally, when I press 5, press 1, release 1, and then release 5, I get

 28:0   Control change          0, controller 104, value 5
 28:0   Control change          0, controller 105, value 5

In this case presses of button 1 are not visible at all. 

Is this a hardware problem or a software problem? In other words, is the device simply not capable of correctly detecting switch presses and releases like this, or is this something that could be fixed in the EurekaPROM?

Many thanks,

-Edsko

[Steven Caldwell]

I think this is a hardware issue on how the FCB1010 reads the switches internally.

[Edsko de Vries]

Ok, I was afraid that might the case. That is unfortunate. Thanks for confirming that Steven!