The scanner does not respond / read bar codes after some time not being used. The scanners seems to intermittently loose its connection. How to disable USB power save mode for the USB hub. The scanner beeps for some reason (boot up sequence) and is unable to scan. The OPOS, JavaPOS, POS4net driver, reports the driver is unable to connect to the scanner. Middleware is occasionally no longer able to claim or connect to the scanner.
In order to confirm the symptoms are related to a USB issue, Honeywell recommends to connect the scanner to a non-USB interface. E.g: connecting it to a serial COM interface to see if the issue should completely disappears.
Honeywell advises to check on a system that does not scan, whether the USB device is still listed in the Windows Device Manager.
If it is confirmed it is a USB related issue, the following is likely happening. The Host system might go into one of its hibernation /standby /screensaver or power save modes. Under these conditions the USB port is suspended to conserve power. Coming out of one of these conditions, the USB port is then temporarily enabled (sounding the scanner's audible boot-up sequence). Because the system does not see any communication from the scanner, the USB port will be suspended again.
If there is any driver control or middle-ware involved to control the scanner (OPOS- JavaPOS, POS4NET- controls), those tools are often unable to wake-up the USB port and simply try to open (or claim) the disconnected scanner. Because the USB port is suspended and the tool fails and reports the scanner to be unavailable. As the scanner is at that point 'disabled' by the middle-ware, it will not be able to scan and wake-up. The port either and only a disconnect re-connect event where the scanner enumerates again will bring the system back to work.
To work around this issue Honeywell advises to disallow the Host system to suspend the USB port. As this differs per OS the following linked attachments demonstrate how to achieve that for the following OS's: