 |
|
|---|---|
|
|
|
 |
|
 |
|
 |
|
 |
|
 |
|
 |
|
 |
|
 |
|
 |
|
 |
|
Issues:
Issue: USB Mighty Rat Works Fine, Then Stops Working.
Cause: The Mighty Rat is a USB Keyboard device with a default status as a High Priority USB Root Hub Device. USB devices with High Priority are supposed to be kept active by the computer 100% of the time, while some other devices are put to sleep when idle. The USB Root Hub waits for an idle device to generate an interrupt request before returning it to active service. This is done to save power.
It appears that in a number of cases, the USB Mighty Rat has INCORRECTLY been allocated a low priority by the system. In that situation if the Mighty Rat sits idle for an appropriate time (around 3 to 5 minutes seems to be the norm) the computer may simply stop looking at it. When the left or right arrow command is triggered it sends an interrupt request to the hub, which then waits for some data to arrive. Unfortunately, the arrow command WAS the data. This not only contravenes the USB protocol, but also common sense. In some instances the USB hub even ignores interrupt requests, and continues to stay idle.
This problem only seems to affect some laptops running Windows XP Service Pack 2. Mac and other Windows platforms are unaffected.
A simple check for USB Mighty Rat & PC compatibility is to test, leave idle for 5 minutes and then test again. If no glitch is experienced then it is unlikely that one will appear later on, but to be safe take the following action.
Fix#1: There's a setting in "Control Panel" > "System" > "Device Manager" for the USB Root Hub components. Under "Universal Serial Bus controllers" > right click "USB Root Hub" select "Properties", and you will see a setting in "Power Management" which allows the USB device to be sent to sleep. Un-checking "Allow the computer to turn off this device to save power" has fixed the problem in all known cases.
If you have multiple Root Hubs listed you should repeat this procedure on all of them.
Fix#2: If the Root Hub is unkind enough to go to sleep DURING a PowerPoint Presentation, then an extra button click should wake it. If that is unsuccessful, we advise that you should pull the Mighty Rat's USB connector from the PC's socket and simply plug it back in again (yes, during the show). That will wake up the Root Hub and put you back in business, and no you won't get a pop up message over the top of your PowerPoint Slide. As soon as possible after the end of the presentation we advise that you instigate Fix#1, which will take about a minute and does not require a restart.
Issue: My Slides Advance Twice on One Click.
Cause: This issue concerns the use of RF slide advancement products in a stand alone configuration, when controlling Notebook Computers with 400MHz Front-Side Bus speeds. Does not affect equipment purchased after February 2006.
Notebooks typically radiate large amounts of RF noise as they are generally cased in plastic and not well shielded. In addition they are often prone to inject noise into the power lines via the power supply, and to top it off, the LCD Screen can even behave as an antenna. In any PC the Front-Side Bus is a notorious generator of RF noise. A computer with a 400MHz Front-Side Bus can produce intermittent components at other frequencies, and if you are unlucky they can sweep through the 433MHz carrier frequency of the RF slide advancement gear. If this occurs during a button press, the result can be that the RF Receiver sees two button clicks instead of one, because the brief burst of in-band noise will interrupt the transmission, which then resumes when the noise goes away. The duration of such a burst is typically less than 100 milliseconds. If you experience this issue then you have a number of choices:
Fix:
- If you own a Cue King you should draw power for the RF Receiver from the Cue King via a microphone cable, and remove the plugpack power supply. The power derived from the Cue King is 12V regulated and has the effect of adding stability to the output section of the RF Receiver. It also blocks anything coming back up the power line. We have not heard of anybody having this issue when connected in this way.
- Change the plugpack to a regulated 12VDC model. (see fix #1)
- Move the RF Receiver away from the source of noise. If the wanted signal is larger than the unwanted noise, then the signal wins. How far? Sometimes 1 Metre, sometimes quite a bit, depending on how prolific is the offender. Sometimes it may be easier to put the RF Receiver down at the stage, and run a mic lead back to your Mighty Rat. The length of this cable run is generally not an issue. Keep in mind that the PC may be infecting the power supply, and plugging into a new circuit may be necessary.
- If you have experienced this issue or are concerned about it, there is a quick and inexpensive factory modification available which renders the receivers immune to this kind of in-band noise. It is recommended that you contact Szikla Technical and quote your receiver's serial number to see if it qualifies. Units purchased after February 2006 feature this modification as standard.
Issue: USB Mighty Mouse occasionally misses a cue.
Cause: USB devices are controlled by a central hub within the PC, which allocates resources in a kind of time share scenario. Depending on BIOS, Hardware and Windows XP device management, certain devices on the USB bus are deemed to be more important than others. The result is that those with high priority such as a keyboard remain active 100% of the time, while other devices are ignored when idle. The USB hub waits for an idle device to generate an interrupt request before returning it to active service. Frequently, the USB Mouse is allocated a low priority by the system. So if the mouse sits idle for the appropriate time (around 3 to 5 minutes seems to be the norm) the computer will stop looking at it. When the left click is triggered it sends an interrupt request to the hub, which then waits for some data to arrive. Unfortunately, the left click WAS the data.
This problem seems to be native to machines running XP and does not seem to occur on other versions of Windows, or Mac OS. It is also worth mentioning that the PS2 Mighty Mice are also immune from this problem, as they populate their very own dedicated port, regardless of machine or system.
A simple check for USB Mouse & PC compatibility is to test, leave idle for 5 minutes and then test again. If no glitch is experienced then it is unlikely that one will appear later on, and all should be fine, but to be safe, take the following action.
Fix: There's a setting in "Control Panel" > "System" > "Device Manager" for the USB Root Hub components. Under "Universal Serial Bus controllers" > right click "USB Root Hub" select "Properties", and you will see a setting in "Power Management" which allows the USB device to be sent to sleep. Un-checking "Allow the computer to turn off this device to save power" has fixed the problem in all known cases.
If you have multiple Root Hubs listed you should repeat this procedure on all of them.
Issue: USB Mighty Rat won't talk to computer.
Cause: The USB Mighty Rat is plug and play compatible but that doesn't mean your computer will recognise it the moment it is plugged in. There has to be a little data handshake before the computer is happy to get on with business.
Fix: Plug the USB Mighty Rat into the computer via a USB port. Activate the Mouse Output on the Cue King and start pressing the Forward and Reverse buttons repeatedly. This will alert the computer and shortly thereafter the devices will operate as normal. In extreme cases it may be necessary to reboot the computer while the USB Mighty Rat is plugged in, but in any case no special software is required and the computer will use its own keyboard drivers.