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Entry  Mon Mar 16 16:07:39 2015, Hermann-Josef Mathes, Running 2 instances of a DRS DAQ program 
    Reply  Tue Mar 17 02:53:26 2015, Stefan Ritt, Running 2 instances of a DRS DAQ program 
       Reply  Thu Mar 19 07:37:52 2015, Daniel Stricker-Shaver, Running 2 instances of a DRS DAQ program 
Message ID: 399     Entry time: Tue Mar 17 02:53:26 2015     In reply to: 398     Reply to this: 400
Author: Stefan Ritt 
Subject: Running 2 instances of a DRS DAQ program 

I never had in mind running two systems in parallel, that's why the code claims all interfaces when started. You have to dig into the usb code which is located in musbstd.c at function musb_open(). There you will find a line libusb_claim_interface() which requests exclusive access to the usb subsystem. The code is there because I copied it from some standard example for the libusb library. You have to read the documentation for libusb (http://libusb.sourceforge.net/api-1.0/) and see if you can get rid of that. Probaby you have to claim/release the interface on each access, but I never tried that.

Stefan

Hermann-Josef Mathes wrote:

Hi,

we want to run two instances of our little DRS DAQ program but obviously the first instance started always claims all DRS boards for itself and the other one exits with an error. The 2 boards used in the example below have the serial number # 2413 and #2414 and are v5 boards.

The first one:

mathes@ikauger5:~/src/DRS4/Cpp> ./drsdaq -b 2413
DRSController: found board with serial number #2413
DRSController: found board with serial number #2414
DRSController: using board with serial number #2413
CalibratedFrequency= 1.00721
====================================
DRS type:            DRS4
Board type:          9
Serial number:       2413
Firmware revision:   21260

...
And the second one:

mathes@ikauger5:~/src/DRS4/Cpp> ./drsdaq -b 2414
musb_open: usb_set_configuration() error -6
musb_open: Found USB device 0x04b4:0x1175 instance 0, but cannot initialize it: please check permissions on "/proc/bus/usb/1/7" and "/dev/bus/usb/1/7"
USB successfully scanned, but no boards found
...


How can our goal be achieved?

Thanks

Hermann-Josef

 

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