[TESTCASE SCENARIO] Does ROS support dynamic LEDs?

[wojo664]

Hello.
I've been thinking of it for some time now. Does the ROS support dynamic LEDs on Keyboard? There are some programs that uses them for showing for example data flow from network card, or in this case a visualisation responding to the music. I've tried this on VBox some time ago, but it didn't work (maybe VBox does not send the LED commands straight to the Keyboard?)

This is what I'm talking about (runs on XP):
http://www.youtube.com/watch?v=sOdkGu6uCrw

This is a plugin for Winamp called Visualisation KEYLED v.2.1

It basically changes the states of the Caps-Lock, Num-Lock and Scroll-Lock in such a way, that it blinks right with the beats of the music (not seen on the video because of small delay)

[PurpleGurl]

Hmmm....that looks interesting. It is not too hard to do either. All you have to do is to send the proper mask to the keyboard light port using AND and OR with the OUT instruction. Hey, I did that years ago in Quickbasic under MS-DOS. I wrote a program to strobe the screen and figured, what the heck, I could strobe the keyboard lights as well.

I don't know why it did't work for you. Maybe your emulator hid or filtered the address needed.

[wojo664]

To clear this up: This is NOT my program

[Peterbjornx]

@PurpleGurl: This wont work in any modern OS as the in and out instructions are restricted to privilege ring 0 (Kernel mode), in DOS, both user applications and the OS run in ring 0, in modern OSes (NTOS,ReactOS,Linux,etc...) only the kernel and some drivers run in ring 0, the user programs are kept in ring 3, which can only use math and program flow instructions, to interface with hardware (even KBD leds) it needs to call the OS kernel.

[PurpleGurl]

@PurpleGurl: This wont work in any modern OS as the in and out instructions are restricted to privilege ring 0 (Kernel mode), in DOS, both user applications and the OS run in ring 0, in modern OSes (NTOS,ReactOS,Linux,etc...) only the kernel and some drivers run in ring 0, the user programs are kept in ring 3, which can only use math and program flow instructions, to interface with hardware (even KBD leds) it needs to call the OS kernel.

You can tell how long it was since I've coded! I am used to real mode, segment architecture, and direct hardware access. I've never coded for protected mode nor its modern cousins. As for how WinAmp can do it, or why ROS cannot do it, I have no idea.

[jcalvarez]

There is a keyboard driver IOCTL for that: IOCTL_KEYBOARD_SET_INDICATORS

Regards,

Jose

[hto]

Does the ROS support dynamic LEDs on keyboard?

The above-mentioned IOCTL is implemented.

There are some programs that uses them for showing for example data flow from network card, or in this case a visualisation responding to the music. I've tried this on VBox some time ago, but it didn't work (maybe VBox does not send the LED commands straight to the Keyboard?)

Could you try it on real hardware? If it will not work, it's indeed a ReactOS bug. Please file a bug report then.