I have developed a kernel extension (KEXT) for my USB bulk device, supporting for Mac OS X 10.4.7+ G4/G5/Intel machines and it works quite well! Thanks for your constant support for this!!
Recently I have enountered a very strange issue and wanted to discuss for the same. Let me try to clear my problem by taking the Ideal scenerio and the scenerio in which I am enountering the issue.
Note: My bulk device can consume maximum of 60mA
============
Ideal Scenerio:
I attach my multiple (2-4 generally) devices to the bus-powered hub which is directly connected to the root. I attach more than 1 my similar devices and plug-in and plug-out the device frequently.
"APPLE_Machine_ROOTHUB<===>ONE_HUB<=>My 2 USB devices attached."
Steps:
a) I attach my 2 usb bulk devices to the hub directly.
b) I plug-out one of my usb bulk device. The other usb bulk device works fine and communicate with the user application without any issues.
Everything works fine as designed!.
============
Problem Scenerio:
a) I cascade 2 hubs.
b) I attach my 2 devices to the last hub.
c) Now when I plug-out my 1 usb bulk device, the other device resets itself !!!
The other device resets itself on removing the first device and my communication with the application also resets at this point of time
:( Why ??
"APPLE_Machine_ROOTHUB<==>ONE_HUB<==>SECOND_HUB<==>My 2 usb devices are attached here"
============
Is this related to hardware i.e. my USB bulk device OR KEXT development OR the hubs OR the Macintosh Power Management System ??
I tested exactly the similar scenerio Windows 2000/XP and it work well without any issues. So as per my knowledge it might not be the issue with the USB bulk device and neither the hubs.
Did anybody enountered such issue before ?
Can you please explain / comment what can be the possible reason ?? If possible, how to resolve this issue ?
Please let me know incase my query is not clear or more info is required.
Thanks and Regards,
Rohit Dhamija
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Usb mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
http://lists.apple.com/mailman/options/usb/email@hidden
This email sent to email@hidden
