java - Serial port over USB in Linux changes unexpectedly -


i have problem custom electronic device communicating workstation via rs232 on usb interface. device connected, receive, says, address /dev/ttyusb0, after (random ) time of sending receive commands, device appear hang. looking @ device events ( dmesg ), found following error:

ftdi_sio ttyusb0: failed modem status: -32 ... usb disconnect, device number 29 [66208.321174] ftdi_sio ttyusb0: ftdi usb serial device converter disconnected ttyusb0 [66208.497613] usb 1-1.5: new full-speed usb device number 30 using ehci-pci [66208.589052] usb 1-1.5: new usb device found, idvendor=0403, idproduct=6001 [66208.589055] usb 1-1.5: new usb device strings: mfr=1, product=2, serialnumber=3

so apparently system notices device disconnection/reconnection, thus, device mounted port, ie /dev/ttyusb1, causing further communication failure. creating test bed changes behavior: error seems appear less frequently, while using complete application error appears recurrently. application uses jssc-2.8.0 communicate serial port. whole application written in java 8, , uses restle library issue rest requests web services. can cause these strange behavior?

added per @darkfalcon comment below, test bed polls device faster real app: possibly explain why test perfors better other.

the problem due power management: box decided device idle , after time removes power. device apparently comes alive again in 0 time. strange behavior


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