Connecting to a Firebox Touchscreen may prevent new USB devices from being detected

Table of Contents :

1. Firebox Display May Prevent USB Devices From Being Detected
2. Suggestions For Mitigating USB Detection Issues

Using the Firebox U41-T150DR-SB Touchscreen may prevent new USB devices from being detected

1. Firebox Display May Prevent USB Devices From Being Detected

Users may report that their systems are unable to detect any new USB devices after a Firebox Touchscreen display is attached to the system. The following symptoms may be observed :

• Any USB devices attached to the system prior to the Firebox display, will be detected and function normally.
• Any USB devices that are attached following the addition of the Firebox display, are not detected and do not function.
• Any USB device that was functioning, but is removed will not function after being re-attached to the system with the Firebox display attached.
• If the system is booted with the Firebox display attached, no other USB device will be detected.
• The USB ports return to normal function when the Firebox display is removed.

The issue was replicated with the Firebox U41-T150DR-SB touchscreen, although this problem may extend to other FireBox touchscreen displays. The issue has been replicated on the following systems :

• Optiplex 790
• Optiplex 990

Back to Top

2. Suggestions for mitigating USB detection issues

Although this is not a Dell hardware issue, the issue has been identified and two workarounds are available. The issue is identified as being due to the Firebox display not releasing the USB Bus after it has enumerated (unlike a standard USB device) thus preventing the further detection of any USB devices attached to the system. This is an issue directly related to the Firebox display. There are two suggestions to help mitigate this issue :

1. Plug the Firebox display into the last USB port. This improves the chance that the Firebox display will be the last USB device detected, allowing the mouse and keyboard to function normally on boot. This option may still allow the USB detection issue to occur after the boot process, preventing further USB devices from being detected after boot.

2. Attach the Firebox display to a USB Hub. When the Firebox display is isolated by a Hub (powered or unpowered), direct access to the USB Bus is prevented and the detection issue does not reoccur. In addition, the remaining USB Ports on the Hub work normally, regardless of the order of USB device detection.

Back to Top