Quote from: garpepi on April 15, 2014, 04:26:34 PM

aaah!! i've tried that one too, but when i plug the 33th device, bfgminer cannot found it >,< but my raspbian has detected 33 device plugged in Sad

Does ubuntu even see the device connect?

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Apr 17 16:43:34 miner01 kernel: [ 4134.488243] usb 1-3.7.4: new full-speed USB device number 24 using ehci_hcd
Apr 17 16:43:34 miner01 kernel: [ 4134.602607] usb 1-3.7.4: New USB device found, idVendor=04d8, idProduct=000b
Apr 17 16:43:34 miner01 kernel: [ 4134.602617] usb 1-3.7.4: New USB device strings: Mfr=1, Product=2, SerialNumber=0
Apr 17 16:43:34 miner01 kernel: [ 4134.602624] usb 1-3.7.4: Product: HEX16B-Bitfury ASIC Miner
Apr 17 16:43:34 miner01 kernel: [ 4134.602630] usb 1-3.7.4: Manufacturer: TECHNOBIT HEX ASIC Miner.
Apr 17 16:43:34 miner01 kernel: [ 4134.603502] cdc_acm 1-3.7.4:1.0: This device cannot do calls on its own. It is not a modem.
Apr 17 16:43:34 miner01 kernel: [ 4134.603591] cdc_acm 1-3.7.4:1.0: ttyACM0: USB ACM device
Apr 17 16:45:14 miner01 kernel: [ 4234.076264] usb 1-3.7.2: reset full-speed USB device number 20 using ehci_hcd
Apr 17 16:45:14 miner01 kernel: [ 4234.301256] usb 1-3.7.2: reset full-speed USB device number 20 using ehci_hcd
Apr 17 16:45:14 miner01 kernel: [ 4234.524290] usb 1-3.7.2: reset full-speed USB device number 20 using ehci_hcd
Apr 17 16:45:15 miner01 kernel: [ 4235.748249] usb 1-3.7.3: reset full-speed USB device number 21 using ehci_hcd
Apr 17 16:45:16 miner01 kernel: [ 4235.972250] usb 1-3.7.3: reset full-speed USB device number 21 using ehci_hcd
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You should see stuff like this.

Connect them 1 by 1, do not start bfgminer, and look at /var/log/syslog. I want to see what it shows when the 33rd is connected.

I found this in the readme of cgminer:

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There may be a limit to the number of USB devices that you are allowed to start.
The following set of commands, followed by a reboot will increase that:

sudo su
touch /etc/sysctl.conf
echo kern.sysv.semume=100 >> /etc/sysctl.conf
chown root:wheel /etc/sysctl.conf
chmod 0644 /etc/sysctl.conf
----

ofcourse first check if that file exists and append the "kern.sysv.semume=100".

rgdz,
bhai